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Jul. 2022, Volume 16 Issue 7

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Cover illustration Targeting at the conflict between growth and production, a dual temperature control system is developed for yeast engineering based on the expression and activity control of the transcriptional activator Gal4, which acts as a switch to regulate the direction of carbon flux. Temperature change serves as an input signal to trigger the expression of the Gal4 mutant under a heat-shock promoter, and meanwhile to activate it due to its cold-sensitive feature. By changing the culture temperature from 30 °C to 37 °C, both the expression level and activity of the Gal4 mutant are increased, which re-directs the carbon flux from cell growth to product synthesis. In this way, the cellular burden caused by isoprene biosynthesis via a mitochondria-compartmented pathway could be relieved, leading to reconstruction of balance between cell growth and isoprene production. (Jiaxi Lin, Zhen Yao, Xiaomei Lyu, Lidan Ye, Hongwei Yu, pp. 1079–1089)

Jun. 2022, Volume 16 Issue 6

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Inspired by the integration process, aluminum hydrogel (alum)-stabilized oil-in-water emulsions (ASEs) was assembled in a modular way. The oil phase was screened thoroughly for the enhanced anti-oxidative capability and long-term-storage stability. Subsequently, alum was adsorbed and packed on the squalene/water interphase, forming the particulate emulsion droplet. With the hydrophobic and electrostatic interactions, the droplet increased the antigen loading efficiency and induced potent antigen-specific antibody secretion and T-cell-mediated immune responses. Furthermore, the acceptable biosafety profile was also elicited. The featured paper also studied the the underlying mechanisms of droplet stability and the boosted immunogenicity, which may offer an alternative strategy for safe, stable, and effective emulsion adjuvants. (see Lili Yuan, Xiao-Dong Gao, Yufei Xia, pp. 973–984)

May. 2022, Volume 16 Issue 5

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(Rongzhen Chen, Xinfei Dong, Qingchun Ge, pp. 755–763)
As draw solute is the core element of forward osmosis (FO), here Li-Bet-Tf2N synthesized from a customized ionic liquid betainium bis(triflfluoromethylsulfonyl)imide ([Hbet][Tf2N]) and Li2CO3 recovered from lithium-ion battery (LIB) wastes is proposed as a draw solute to treat Li+-containing wastewater from LIB manufacturing through FO filtration. Li-Bet-Tf2N generates a sufficiently high osmotic pressure to drive the FO separation efficiently. Li-Bet-Tf2N produces a water flux of 21.3 L·m−2·h−1 at 1.0 mol∙L‒1 against deionized water, surpassing conventional NaCl and MgCl2 draw solutes with higher water recovery efficiency. Moreover, Li-Bet-Tf2N induces higher water permeation flux with a 10.0% water flux decline than NaCl and MgCl2 for which the water flux decline 16.7% and 16.4%, respectively, in treating 2000 mg∙L‒1 Li+-containing wastewater for 12 h. Remarkably, unlike other draw solutes which require intensive energy input in recycling, Li-Bet-Tf2N is easily separated from water via solvent extraction. Li-Bet-Tf2N thus demonstrates a novel class of draw solute with great potentials to treat wastewater economically.

Apr. 2022, Volume 16 Issue 4

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(Jinian Yang, Xuesong Feng, Shibin Nie, Yuxuan Xu, Zhenyu Li, pp. 484–497) Due to the intrinsic drawbacks of relatively high brittleness and poor wear resistance, epoxy products cannot undergo the rubbing actions under dry sliding and hard to be sate when served as engineering parts. Yang et al. propose a promising solution to solve the above problem by introducing low-content flower-like nickel phyllosilicates to yield the cost-effective epoxy nanocomposites with highly restricted abrasions. Flower-like particles are well-constructed firstly and then served as effective reinforcements to enhance the mechanical, thermal and tribological properties, and finally the possible wear mechanism involved in present friction process is discussed thoroughly. This study attempts to provide a facile route for the development of high-performance epoxy-based friction materials.

Mar. 2022, Volume 16 Issue 3

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(Hongtao Xie, Qin Geng, Xiaoyue Liu, Jian Mao, pp. 376–383)
Rational design of highly efficient electrocatalysts for oxygen evolution reaction (OER) is critical for sustainable energy conversion. Herein, a novel bijunction CoS/CeO2 OER electrocatalyst grown on carbon cloth is prepared through electrodeposition. Such a CoS/CeO2/CC electrocatalyst exhibits outstanding OER catalytic activity with a low overpotential of 311 mV at 10 mA•cm−2 and a low Tafel slope of 76.2 mV•dec−1. This is because the interface engineering of CoS and CeO2 facilitates charge transfer and active sites and the rich oxygen vacancies of CeO2 film promote the absorption of oxygen species in the medium.
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Feb. 2022, Volume 16 Issue 2

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(Teng Zhou, Kai Sundmacher, pp. 137−140)
A process system can be generally decomposed into hierarchical levels or scales at which different physical and/or chemical phenomena take place.

Jan. 2022, Volume 16 Issue 1

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(Yongqing Zhou, Xin Wang, Wei Zhang, Bo Tang, Ping Li, pp. 4–33)
Fluorescent technology associated with small molecular probes have been widely used for studying of molecular events in biological systems due to its excellent performances, including noninvasive, high sensitivity and selectivity, and high spatial temporal resolution. Particularly, small molecule fluorescent probes have been successively developed to simultaneously monitor two biomolecules to uncover their interrelationships and synergistic regulations in related diseases. In this review, we focus on summarizing the design strategies, classifications, and bioimaging applications of dual-response small molecule fluorescent probes over the past decade. Furthermore, challenges and future research directions in this field are proposed in brief.

Dec. 2021, Volume 15 Issue 6

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(Hao-Yu Wang, Chen-Chen Weng, Jin-Tao Ren, Zhong-Yong Yuan, pp. 1408–1426)
The development of earth-abundant electrocatalysts for hydrogen production from low-grade and saline water with renewable electricity is highly desired but very challenging due to the interference of side reactions and various impurities. Yuan et al. give a conceptual understanding of direct seawater splitting with the difference to the electrolysis in pure water. Effective strategies for the rational construction of electrocatalysts with improved selectivity and stability on both anode and cathode based on possible electrochemistry involved in this process are discussed, including thermodynamically restricting chloride chemistry, designing selective active species and constructing protecting layers. Rational design of highly efficient and stable electrolysers is also required for the implement of direct seawater electrolysis. For the guidelines of future research, recent achievements are discussed and issues to be solved are provided.
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Oct. 2021, Volume 15 Issue 5

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(Hui Shang, Chong Guo, Pengfei Ye, Wenhui Zhang, pp. 1088‒1098)
The development of hydrodesulfurization (HDS) technology is urgent for the production of clean gasoline due to the strict environmental regulations. Major challenge is to increase the HDS performance while reduce the hydrogenation of olefins, which contributes a lot gasoline octane number. The special interaction between microwave and the material’s molecules highlights the obvious advantages by using microwave in the area of HDS of petroleum oils. The HDS catalyst prepared by microwave heating presents enhanced properties as enlarging the surface area, reducing the acidity of the support, improving the stacking numbers of the active components, all of which contributes to higher HDS performance. The study of the synergistic effect between microwave and catalyst is the key to microwave high efficiency HDS technology, which is of great significance to the production of ultra-low sulfur clean gasoline.
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Aug. 2021, Volume 15 Issue 4

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(Wei Wang, Yanying Wei, Jiang Fan, Jiahao Cai, Zong Lu, Li Ding, Haihui Wang, pp. 793‒819)
Membrane-based separation technologies have received increasing attention attributing to lots of advantages such as the low energy consumption, easy operation, and environmental friendliness. Two-dimensional (2D) materials have emerged as a class of promising materials to prepare high-performance 2D membranes for various separation applications. The precise control of the interlayer nano-channel/sub-nanochannel between nanosheets or the pore size of nanosheets within 2D membranes enables 2D membranes to achieve promising molecular sieving performance. To date, many 2D membranes with high permeability and high selectivity have been reported, exhibiting high separation performance. This review presents the development, progress, and recent break-through of different types of 2D membranes, including membranes based on porous and non-porous 2D nanosheets for various separations. Separation mechanism of 2D membranes and their fabrication methods are also reviewed. Last but not the least, challenges and future directions of 2D membranes for wide utilization are discussed in brief.
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Jun. 2021, Volume 15 Issue 3

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(Yingying Jian, Danyao Qu, Lihao Guo, Yujin Zhu, Chen Su, Huanran Feng, Guangjian Zhang, Jia Zhang, Weiwei Wu, Ming-Shui Yao, pp. 505‒517)
Ti3C2Tx MXene, a two-dimensional (2D) materials with ultra-thin structure, has been fabricated as gas sensors working at room temperature with various thickness. In this work, two critical features towards reducing gases (NH3 and CO) and oxidizing gas (NO2) are characterized in a dynamic model. On one hand, the thickness of the Ti3C2Tx MXene material affects the sensing performance that the response to gases is declined with the increasing thickness of the Ti3C2Tx MXene. On the other hand, the Ti3C2Tx MXene based gas sensor is not appropriate for strong and moderate oxidizing gas (NO2) compared with the reducing gases (NH3 and CO). These two rules are demonstrated, and could be considered with priority both in the future researches and practical applications.
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Apr. 2021, Volume 15 Issue 2

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(Fernando F. Rivera, Berenice Miranda-Alcántara, Germán Orozco, Carlos Ponce de León, Luis F. Arenas, pp. 399‒409)
Redox flow batteries are being developed to contribute to the large-scale energy storage required for the full implementation of renewable energy sources. A grid incorporating energy storage is capable of managing the load-levelling needs set by wind and solar power. Among the proposed chemistries, cerium-based systems are interesting due to their relatively high cell voltage. Our work presents validated CFD simulations of two relevant materials for the positive electrode of this device: a 2D planar electrode (and a polymer mesh spacer) and a 3D expanded metal mesh. Turbulent Reynolds-averaged Navier-Stokes and free flow plus porous media models were applied to compute local fluid velocities within a rectangular channel flow cell for laboratory studies. Calculated pressure drop was compared to experimental data. Pressure drop was described by the RANS approach, whereas the validity of Brinkman equations was dependent on the permeability of the porous media.
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Feb. 2021, Volume 15 Issue 1

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(Faraz Montazersadgh, Hao Zhang, Anas Alkayal, Benjamin Buckley, Ben W. Kolosz, Bing Xu, Jin Xuan, pp. 937‒947)
The cover image shows the vision of our e-bio-fuel project, joint funded by the UK’s Department of Transport and SuperGen Bioenergy Hub in 2019. It aims to develop a new electrochemical platform to produce low-carbon fuels through integrated co-valorisation of biomass feedstocks with captured CO2. In this approach, CO2 is reduced at the cathode to produce drop-in fuels while value-added chemicals and fuels are produced at the anode from selective oxidation of bio-feedstocks. Our vision is to intensively increase the sustainability of the road transport sector, while enhancing renewable energy security.
In this work, a numerical model of a continuous-flow e-bio-fuel electrochemical reactor considering various anodic and cathodic reactions was built to determine the most techno-economically feasible configurations from the aspects of energy efficiency, environment impact and economical values. The reactor design was then optimized via parametric analysis. Through the study, the feasibility of our e-bio-fuel process has been proven.
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Dec. 2020, Volume 14 Issue 6

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(Mehraneh Ghavami, Mostafa Aghbolaghy, Jafar Soltan, Ning Chen, pp. 937‒947)
Volatile organic compounds (VOCs) are among the major sources of air pollution. VOCs in indoor air are released from human activities and a wide variety of materials such as cleaning agents, floorings, paints, surface coatings, and furniture. Using ozone in catalytic oxidation of VOCs is a potential air treatment method with benefits such as decreasing reaction temperature and possibility of using transition metal oxides instead of precious metals.
We studied catalytic ozonation of acetone over a series of alumina supported single and mixed Mn-Co oxides catalysts at room temperature. Alumina acts as a reservoir for acetone and it interacts with acetone to create surface carboxylate intermediates. Surface carboxylates migrate to the metal sites and react with highly active atomic oxygen species produced from ozone decomposition. The intermediates are oxidized on the metal sites to produce CO2 and water.
The addition of lower loading of Co as secondary metal to Mn catalysts improved activity of the catalysts significantly. By augmenting the catalyst with the second metal with lower loading, the local structure and oxidation states are affected. Catalysts having lower oxidation states are more active in transferring electrons to ozone, leading to higher ozone decomposition, and thus enhanced acetone oxidation.

Oct. 2020, Volume 14 Issue 5

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(Zhaoyou Zhu, Guoxuan Li, Yao Dai, Peizhe Cui, Dongmei Xu, Yinglong Wang, pp. 824‒833)
The traditional approach of solvent selection in the extractive distillation process strictly focuses on the change in relative volatility of the light-heavy component caused by the solvent. However, the total annual cost of the process may not be minimal when the solvent causes the greatest change in relative volatility. This work presents a heuristic method to select the optimal solvent to minimize the total annual cost. The functional relationship between the relative volatility and the total annual cost is established, where the main factors, such as the relative volatility of the light-heavy component and relative volatility of the heavy-component solvent, are taken into account. Binary azeotropic mixtures of methanol-toluene and methanol-acetone are separated to verify the feasibility of the model. The result shows that the total annual cost of the process by using the solvent with the minimal two-column extractive distillation index is the lowest. This study provides a rapid and effective design strategy for the preliminary selection of solvents in extractive distillation.

Aug. 2020, Volume 14 Issue 4

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(Anna Khlyustova, Nikolay Sirotkin, pp. 513‒521)
Benzoic acid is used in textiles, plastics, chemicals, powders, catalyst, and for wood bleaching. The solutions of benzoic acid are corrosive, toxic and poisonous and they should be removed from water. Plasma in contact with liquids is one of the methods of advanced oxidation processes. Plasma treatment can lead to destruction as well as synthesis processes. It was proved in the experiments with benzoic acid. At the small time of treatment the mono- and dihydroxyderivatives of benzoic acid are formed. At the long time of treatment, benzoic acid is destroyed via formation of quinones.

Jun. 2020, Volume 14 Issue 3

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(Cyrine Ayed, Wei Huang, Kai A. I. Zhang, pp. 397‒404)
A hybrid material consisting of a covalent triazine framework and mesoporous silica was designed and used as visible light-active, highly efficient, stable and reusable photocatalyst in water. Due to the high surface area and the added hydrophilic properties by silica, the hybrid material demonstrated excellent adsorption of organic molecules in water, leading not only to high photocatalytic performance of the hybrid material for the degradation of organic dyes in water, but also for efficient photocatalysis in solvent-free and solid state in air.

Apr. 2020, Volume 14 Issue 2

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(Yujie Ban, Meng Zhao, Weishen Yang, pp. 188‒215)
CO2 capture is a hot topic in research and industry. It typically refers to the splitting of CO2/N2, H2/CO2 and CO2/CH4, and is one of the most desirable separation technologies in environment and energy sectors. Membrane-based separations are energy-efficient separation methods cutting the energy consumption of traditional distillation by nearly 90%, which offers hope for CO2 capture. Metal-organic frameworks (MOFs) are a versatile platform with compositional and structural tunability, lighting the concept from precise material design to membranes for high-efficiency CO2 capture. This review summarized compositional/structural design and regulation strategies of MOFs targeted at secondary building units (metal nodes and linkers), pore structure, topology and mixed-phase hybrid structures for achieving CO2-philic MOF materials. And diversified methods were illustrated for construction of improved MOF membranes that can overcome the bottleneck of permeability-selectivity limitations.

Feb. 2020, Volume 14 Issue 1

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(Lloyd C. Murfin, Carlos M. López-Alled, Adam C. Sedgwick, Jannis Wenk, Tony D. James, Simon E. Lewis, pp. 89‒95)
Our submission highlights the lifecycle of our azulene-derived chemodosimeter, used for the sensing of nitrite in pork. Sodium nitrite, NaNO2, is a commonly used preservative for red meats, and has gained media attention through its associated carcinogenicity. On our cover image, the pigs are being preserved with their NaNO2 space suit, before blasting off into space. On their travels, they visit three lanterns, which each represent the three colour changes our dosimeter turns in the presence of nitrite. Through the use of colourful lanterns and pigs, we wanted to highlight the Chinese Year of the Pig in tandem with telling the story of our sensor.

Dec. 2019, Volume 13 Issue 4

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(Evelyn Chalmers, Yi Li, Xuqing Liu, pp. 684-694)

Sep. 2019, Volume 13 Issue 3

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(Bin Xu, Toshiro Kaneko, Toshiaki Kato, pp. 517-524)
This cover figure shows an innovative growth method of SWNTs with narrow-chirality distribution, named pulse plasma chemical vapor deposition (CVD). The growth yield of the SWNTs could be improved by repetitive short duration pulse plasma CVD, while maintaining the initial narrow chirality distribution. This study on the precise time-scale incubation dynamics controlling the growth of SWNTs during pulse plasma CVD offers novel insights for the development of chirality-controlled SWNTs.

Jun. 2019, Volume 13 Issue 2

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(Rusen Zhou, Renwu Zhou, Xianhui Zhang, Kateryna Bazaka, Kostya (Ken) Ostrikov, pp. 340-349)
Electrifying chemical industry for cleaner future
Plasma technology is one of the most promising innovations to electrify the chemical engineering field with applications varying from pollution abatement to energy conversion. New engineering solutions are poised to arise based on synergistic plasma effects. In this issue, Zhou et al. demonstrate that synergizing a dielectric barrier discharge plasma water bed with activated carbon adsorption allows large amount of wastewater to be treated to meet drainage standards while reducing treatment time and energy consumption. This effort reveals how collaboration across chemical engineering and plasma applications can contribute to the solution of persistent environmental and energy problems and to create a cleaner, greener and more sustainable planet.

Feb. 2019, Volume 13 Issue 1

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(Dongjie Yang, Shengyu Wang, Ruisheng Zhong, Weifeng Liu, Xueqing Qiu, pp. 630-642)
Lignin is one of the most abundant biomass resources and it makes up 20 wt-%‒30 wt-% of lignocellulose. It endows plants with their natural toughness and UV resistance. The pulp and paper pulping industry generates more than 50 million tons of technical lignin annually. However, most of the technical lignin is not properly utilized. Lignin is renewable, biodegradable, non-toxic, inexpensive and widely available, so the efficient and comprehensive utilization of lignin is of great significance to sustainable chemical industry. For the first time, a simple and effective sol-gel method has been developed for the preparation of lignin/TiO2 nanocomposites in an aqueous medium. The as-prepared lignin/TiO2 nanocomposites contain well-dispersed small particles with excellent UV shielding ability and good compatibility with waterborne polyurethane (WPU). When the lignin/TiO2 nanocomposites were blended with WPU, the tensile ductility, the UV absorbance and anti-UV aging performance of the WPU films increased significantly. This work highlights new possibilities for the utilization of alkali lignin.

Jan. 2019, Volume 12 Issue 4

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(Timothy G. Walmsley, Nathan S. Lal, Petar S. Varbanov, Jiří J. Klemeš, pp. 630-642)
Ever increasing energy costs and environmental concern drives a cycle of continuous process energy improvement in the chemical and process industries. To remain competitive in the short-term and sustainable in the long-term, industrial companies and sites need to identify projects to retrofit and revamp their technology to keep pace with more energy-efficient new plants. Such options include disruptive projects (e.g., new reactor installation) or incremental improvement (e.g., new heat exchangers). Due to the capital intensity of disruptive change, most companies favour incremental, low-risk improvements to stay viable.
Our research focuses on developing techniques to analyse existing processing plants, understand its heat transfer operations and flows, and identify options to improve its energy efficiency. We call our new method the Automated Retrofit Targeting (ART) algorithm. A unique feature of the algorithm is the comprehensive search function that systematically looks at all possible pathways to save energy starting from the current network of operations. We presented a case study on a section of a refinery (27 streams and 46 existing heat exchangers) and found over 68903 feasible, unique retrofit opportunities. The most promising of these retrofit projects required 3 new heat exchanger units and reduced steam use by 4.24 MW.

Sep. 2018, Volume 12 Issue 3

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(Walter Kaminsky, pp. 555-563)
The cover page shows a computer model of a unit structure of methylaluminoxane (MAO). The unit structure contains 4 aluminum atoms, separated by 3 oxygen atoms and 6 methyl groups and associate to larger cages. MAO is the most important cocatalyst to activate transition metal complexes such as metallocens for the polymerization of olefins. The metallocene/MAO catalyst is soluble in hydrocarbons and can be varied by changing the molecular structure of the metal complex (single site catalyst). The activity is about 10 times higher than that of classical Ziegler-Natta catalysts. Today more than 10 million tons of polyethylene and ethylene/propylene copolymers are produced per year by MAO containing catalysts.

May. 2018, Volume 12 Issue 2

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(Adam C. Sedgwick, Alex Hayden, Barry Hill, Steven D. Bull, Robert B. P. Elmes, Tony D. James, pp. 311-314)
The cover shows carrot spacecraft piloted by rabbits.
Link between the picture and the science contained in the paper: Umbelliferone a coumarin fluorophore was used to prepare the sensor employed in this project and is found in carrots. When our sensor reacts with the nitoreductase (NTR) enzyme it releases the fluorescent blue umbelliferone molecule. Nitroreductase (NTR), is one of a series of biomarkers that have been shown to be significantly upregulated in cells under hypoxic stress. Hypoxia is a condition where cells are deprived of adequate oxygen.
Therefore the picture is set in space with the moon representing a cell under hypoxic stress. Therefore, the carrot spacecraft burrowing into the moon change from orange to blue representing the release of the fluorescent blue umbelliferone under hypoxic conditions. The Earth has normal oxygen levels and so no carrot spacecraft have targeted the earth. Importantly, even if they had targeted and burrowed into the Earth they would have remained orange due to the normal oxygen levels.

Feb. 2018, Volume 12 Issue 1

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(Dongxu Han, Zhiguo Zhang, Zongbi Bao, Huabin Xing, Qilong Ren, pp. 113‒123)
Bimetallic nanocatalysts not only combine the properties of individual constituents but also may have enhanced catalytic activity, selectivity, and stability. This may be attributed to the modulation of the charge transfer between different metals and surface element distribution. Thus, the development of bimetallic nanoparticles, in particular, palladium with non-noble metals, has long proven value in the past few years. Among Pd-non-noble metal NPs reported, Pd-Ni NPs have demonstrated to be efficient and economic catalysts for diverse transformations. In this paper, we successfully prepared TiO2-supported Pd-Ni nanoparticles with the mean diameter of approximately two nanometers through a one-step impregnation reduction route. The as-prepared Pd-Ni/TiO2 exhibited enhanced catalytic activity compared to an equal amount of Pd/TiO2 as well as excellent stability, recyclability and applicability in the Suzuki-Miyaura reactions. The catalytic results show that the substrate iodobenzenes and phenylboronic acids bearing with either electron-donating or electron-withdrawing groups gave the corresponding product in excellent yields. Besides, there was no considerable loss in catalytic activities of the Pd-Ni/TiO2 catalyst after four recycles. Moreover, among these Pd-Ni/TiO2 catalysts with different compositions of Ni and Pd, the one with the Ni:Pd ratio of 2.95 showed the best activity.

Nov. 2017, Volume 11 Issue 4

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(Xiaobin Jiang, Linghan Tuo, Dapeng Lu, Baohong Hou, Wei Chen, Gaohong He, pp. 647-662)
Development of membrane science and technology gives more inspiration to chemical engineering researchers in variety of fields. Membrane distillation crystallization (MDC) is a promising hybrid separation process that has been applied to seawater desalination, brine treatment and wastewater recovery. In recent years, great progress has been made in MDC including the promotion of nucleation control of crystallization and crystal size distribution modification. The progress is not only shed light on chemical industry, but also biological and pharmaceutical engineering, etc. Membrane assisted approach provides an alternative approach for the controllable and stable the supersaturation degree and nucleation control. In addition, allowing for the potential integrated MDC with other processes, the development of MDC process models and controlling strategies design should be paid intensive attention. By summarizing the most important innovative applications in MDC, which are developed for crystal engineering and pharmaceutical manufacturing, this review is aimed to overview the progress in MDC and outline the future research direction and potential applications.

Aug. 2017, Volume 11 Issue 3

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The authors of Special Topic on environment and sustainable development come from China, USA, Canada, Italia, the Netherlands and Belgium, thereby forming a union of chemical engineering from China, Europe, and North America.

May. 2017, Volume 11 Issue 2

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(See Yong Zhu, Zhishan Bai, Bingjie Wang, Linlin Zhai, Wenqiang Luo, pp 238-251)
The novelty of this article is focusing on the synthesis method of microfluidic technology. Microfluidic technology occupies high position in product control for the controllable size, structure, component and morphology. The key part of microfluidic equipment is the chip. The continuous phase was pumped into microfluidic chip to sheer dispersed phase at the cross aisle. Dispersed phase necked first under extrusion and shear force, and then it drew and broke into a spherical microsphere finally for its own surface tension. The microsphere flowed through outlet steadily and uniformly into a beaker filled with solidification bath for crosslinking. These microspheres would become impact, stable and plastic after crosslinking. Prepared microspheres were extremely monodispersed, uniform-sized, highly spherical and smooth-faced. The CV value of these prepared microspheres in our work is 1.52%, greatly lower than those CV of microsphere prepared with membrane emulsification or suspension polymerization approaches which were usually about 10%. High monodispersed microspheres could separate out of medium completely or be convenient to handle. The adsorption behavior of these microspheres towards copper (II) and main influencing factors on adsorption performance had been investigated by batch experiments. These microspheres also showed excellent adsorption selectivity and renewability. All these researches provided a brand new direction for preparing highly comprehensive performance sorbent via microfluidic technology.

Mar. 2017, Volume 11 Issue 1

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(Ting Yuan, Yakun Guo, Junkai Dong, Tianyi Li, Tong Zhou, Kaiwen Sun, Mei Zhang, Qingyu Wu, Zhen Xie, Yizhi Cai, Limin Cao, Junbiao Dai, pp. 107-116)
One critical step in metabolic engineering is to optimize, both spatially and temporally, the expression of key enzymes, maximizing the metabolic flux to a desired product. Here a genome-wide collection of native promoter libraries were constructed to drive the expression of a yellow fluorescent protein (YFP) reporter in Saccharomyces cerevisiae, allowing fast and accurate measurement of activity of each promoter with fluorescence activated cell sorting (FACS) followed by next-generation sequencing. Most important of all, the activity of these promoters under different growth conditions and in various host cells could be measured, which allows the identification of promoters specifically suitable for certain industrial applications. As a proof of principal, a set of promoters was selected to construct the metabolic pathway to increase ethanol production using xylose as carbon source. The same strategy could be applied to optimize the production of many other natural products.

Nov. 2016, Volume 10 Issue 4

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(Renxing Wang, Zhenyu Liu, Leiming Ji, Xiaojin Guo, Xi Lin, Junfei Wu, Qingya Liu, pp. 517-525)
Production of calcium carbide (CaC2) from coal-derived coke and lime is still an important coal-to-chemical process today. The autothermal technologies with pulverized coke and lime or pelletized feed have been developed for this process in recent years to replace the traditional electric arc technology due to reduction in energy consumption and CO2 emission. Reaction kinetics of these feeds required for simulation and design of reactors and process are limited and contradictive in the literature. Based on the reaction data obtained by TGA at 17001850°C applicable to industry, the kinetic model is determined with the isoconversional and model-fitting methods. It is found that the process is mainly influenced by heat transfer from the environment to the feed. The larger geometrical surface area of the powder feed yields a higher CaC2 formation rate in comparison with the pelletized feed. The reaction kinetics of both feeds can be described by the contracting volume model. The apparent activation energy and the pre-exponential factor of the pulverized feed are 353 kJ∙mol−1 and 5.9 × 107 min−1, respectively, while those of the pelletized feed are 305 kJ∙mol−1 and 3.6×106 min−1, respectively.

Aug. 2016, Volume 10 Issue 3

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(Dae Hwan Shin, Yu Tong Tam, Glen S. Kwon, pp. 348-359)
Several amphiphilic block copolymers (ABCs) have been widely studied for drug solubilization that enables safe intravenous administration of anticancer drugs, including PEG-b-PLA, PEG-b-poly(propylene glycol)-b-PEG (i.e., Pluronics®), PEG-b-poly(ε-caprolactone) (PEG-b-PCL) and PEG-b-poly(α-amino acid). Proven safety of ABCs is paramount for intravenous administration, along with other major requirements that include sterility, stability, solubility and scale-up. ABCs tend to disrupt cellular membranes less than low molecular weight surfactants, such as Cremophor EL, and undergo renal clearance that limits accumulation in the body, increasing safety. While the primary driving force for drug solubilization is hydrophobic interaction, polarity and hydrogen bonding play parts in governing interaction between drug and core region of polymeric micelles. Thus, structural diversity of core-forming blocks of ABCs permits drug solubilization of a variety of poorly water-soluble anticancer agents; for example, camptothecin, paclitaxel, resveratrol and valspodar, increasing water solubility by 103-fold.

May. 2016, Volume 10 Issue 2

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(Jasna Brčić, Janez Plavec, pp. 222-237)
Amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD) are two related neurodegenerative diseases with devastating consequences. Largely increased number of GGGGCC repeats located within the first intron of C9orf72 gene was identified as the most frequent genetic cause of ALS and FTD. It was proposed that G-quadruplexes formed in the DNA strand of the expanded GGGGCC repeat cause transcriptional pausing and abortion, which leads to accumulation of abortive G-quadruplex forming RNA transcripts. In addition to RNA transcripts being toxic, evidence suggests that they can undergo RAN (repeat-associated non-ATG) translation producing potentially harmful dipeptide repeat proteins. Initial NMR investigation of DNA oligonucleotides with four repeat units chosen as the shortest model with the ability to form a unimolecular G-quadruplex indicated their folding into multiple G-quadruplex structures in the presence of K+ ions. We set to reduce the structural polymorphism by directing the folding towards the most stable naturally occurring G-quadruplex structure. Several approaches were used to drive a complex equilibrium, including point mutations, different folding conditions and use of conformationally constrained 8Br-dG residue. Oligonucleotide d[(G4C2)3GGBrGG] bearing a single dG to 8Br-dG substitution at position 21 formed a single G-quadruplex structure at pH 7.2, which allowed its unequivocal structure determination.

Feb. 2016, Volume 10 Issue 1

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(Nadeen Al-Janabi, Abdullatif Alfutimie, Flor R. Siperstein, Xiaolei Fan, pp. 103-107)
Metal-organic frameworks (MOFs), as versatile and promising adsorbents, have attracted much attention for gas adsorption and separation due to their high adsorption capacity and tuneable structural/chemical properties. Coordinatively unsaturated divalent metal cations (or open metal sites, OMSs) in certain MOFs, e.g. unsaturated copper centres in Cu3(BTC)2 MOF, have been recognised as the attractive feature for gas adsorption. These OMSs render an exceptionally high surface density (e.g. ~3 OMSs per 100 A) leading to particularly high affinity to polar molecules such as water. Therefore, understanding the hydrothermal stability of MOFs with OMSs under appropriate conditions is necessary to enhance the uptake of MOFs for practical applications, e.g. the CO2 capture from flue gases where ca. 7% H2O is present. Here, a case study of water vapour adsorption on Cu3(BTC)2 MOF is conducted revealing its deformation dynamics under humid conditions. Comprehensive post-adsorption characterisation of materials provides evidence, for the first time, for the underlying mechanism of how the water vapour degrades MOFs with OMSs. The result of this research is crucial to guide the ultimate design of future MOFs with superior hydrothermal stability, while maintaining the properties of interest.

Nov. 2015, Volume 9 Issue 4

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(Xinxiang Cao, Arash Mirjalili, James Wheeler, Wentao Xie, Ben W.-L. Jang, pp. 422-449)
Alumina supported Cu-Pd single atom alloy catalysts have been synthesized using galvanic replacement and simple traditional incipient wetness techniques. The single atom alloy structure is evidenced by the HAADF-STEM and H2-chemsorption results. These two techniques can be further used as complimentary methods to confirm the formation of other single atom alloys on common industrial supports. The Cu-Pd catalysts synthesized show excellent selectivity and good activity for the selective hydrogenation of acetylene in ethylene due to the unique function of alloyed single Pd atoms to dissociate hydrogen molecules and transferthem to the neighboring Cu atoms for selective hydrogenation.On the other hand, the overall performance, including catalytic stability,of Cu-Pd catalysts is strongly tied to the synthesis procedure dictating how single atom alloy structure is formed.

Sep. 2015, Volume 9 Issue 3

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Special Issue dedicated to the 120th anniversary of Tianjin University

Jul. 2015, Volume 9 Issue 2

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(See Kathryn A. MUMFORD, Yue WU, Geoffrey W. STEVENS. pp 125-141)
 The capture of carbon dioxide (CO2) from large point sources and subsequent storage underground, utilization for enhanced oil recovery processes or use in chemical synthesis, is essential if CO2 emissions to the atmosphere are to be reduced in the short term. Amongst all CO2 capture technologies currently available, solvent absorption is regarded as the most likely to be used in this large scale application, primarily due to the maturity of the technology and history of successful industrial application. Before widespread implementation is likely, the cost of CO2 capture needs to be reduced. This will be achieved through the development of improved solvents that exhibit; higher CO2 absorption capacities; faster reaction kinetics; limited degradation; and reduced regeneration energies. Here, a timely review of the progress of various solvents for the capture of CO2, from the bench scale, to pilot scale and on to commercial scale installations is provided.

Apr. 2015, Volume 9 Issue 1

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See Huali WANG, Hena FAROOQI, Jinwen CHEN, pp 64–76
The production and consumption of transportation fuels is one of the major contributing factors for global greenhouse gas (GHG) emissions. It is considered that biomass derived fuels from renewable sources have the potential to help reduce GHG emissions and other environmental impacts provided that they are produced in a sustainable way based on their life cycle assessment. To diversify energy supply and to reduce GHG emissions, many countries have implemented mandatory regulations whereinthe total fuel products must contain certain percentages of biofuels or renewable products. Co-processing petroleum with biomass derived feedstocks offers a number of advantages since it uses existing refining configurations, processes and technologies, and needs little or no extra capital investment. In addition, it has the potential to generate synergies between aromatic petroleum feedstocks—especially Canadian oil sands derived crudes—and paraffinic biomass feedstocks for improved fuel quality and product yields. Therefore, co-processingis one of the most attractive and practical options for petroleum refineries to implement in order to meet government regulations and engine fuel standards. However, technological and operational challenges are expected and need to be addressed in actual implementation and operation of co-processing. This study presents a great effort to address some of these challenges.