CANADIAN JOURNAL OF CHEMICAL ENGINEERING
·
2017
·Vol. 96
·期 3
·679-687
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IF 1.356
Zhongrui Liang,Lichao He,Wenchao Wang,Zhiyong Zhou,Zhongqi Ren
Tuberculosis is a serious bacterial infection in developing countries, especially in areas with drug resistance. The development of the anti-tuberculosis drug ethionamide (ETA) is therefore particularly important. We have designed a new route for ETA synthesis and considered the drug's amenability to large-scale manufacture. We evaluated different routes for the synthesis of ETA and selected the most suitable process for the industrial production of this material, which involved the Minisci reaction of 4-cyanopyridine with propionic acid using a AgNO 3 /(NH 4 ) 2 S 2 O 8 catalyst system under acidic conditions. The effects of different parameters on the reaction were studied, and the production of the intermediate of 2-ethyl-4-cyanopyridine was twice recrystallized from methanol to obtain pure ETA. In the Minisci reaction, the system was stirred for an additional 20 min at 80 °C after the addition of ammonium persulphate solution. The subsequent formation of thioamide was conducted at 40 °C to 60 °C for 1.5 h with a 1:5:2 molar ratio of 4-cyanopyridine, propionic acid, and ammonium sulphide. The purity of the crude ETA reached 98.77 % after two recrystallization steps. This process could be scaled up on a much larger scale (1 kg), leading to the yield of alkylation reaction and overall yield of the production process as 44.06 % and 31.26 %, respectively.
研究领域:
药物化学
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有机合成
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结核病研究
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高影响因子
JOURNAL OF MATERIALS SCIENCE-MATERIALS IN ELECTRONICS
·
2023
·Vol. 34
·期 24
·1-19
·
IF 2.8
Chen Haixue,Wang Xinyue,Zeng Zejun,Zhang Guoqi,Zhang Jing,Liu Pan
With the development of electronic technology towards high power, miniaturization, and system integration, power electronic packaging is facing increasing challenges, especially for die attachment. This research aims to explore silver-coated copper (Cu@Ag) paste with sufficient mechanical properties and high-temperature reliability, as an alternative solution for silver sintering with lower cost. Firstly, micro-Cu@Ag sintering pastes were investigated under four kinds of polyol-based solvent systems and two types of particle morphologies, which included sphere-type (SCu@Ag) and flake-type (FCu@Ag). Sintering performance and microstructural evolution were compared and analyzed. Notably, sintered joints employing the terpineol–polyethylene glycol solvent system and flake-type morphology displayed a denser microstructure in comparison to SCu@Ag joints. Its bonding strength reached 36.15 MPa, which was approximately 20% higher than SCu@Ag joints. Subsequently, the influence of key sintering process parameters on Cu@Ag joints was analyzed, including sintering temperature, pressure and time. Additionally, high-temperature aging and thermal cycling tests were conducted on the optimized Cu@Ag joints to assess their reliability. Finally, the micromechanical properties of Cu@Ag joints before and after high-temperature aging were further evaluated by nanoindentation including creep properties. The elastoplastic constitutive models of Cu@Ag sintered materials with different particle morphologies were constructed, providing valuable insights for reliability evaluation. The results indicated that FCu@Ag joints exhibited satisfactory creep resistance and high-temperature reliability. In conclusion, the FCu@Ag micro-paste based on the terpineol–polyethylene glycol solvent system proposed in this study demonstrated sufficient bonding strength, high reliability, and adequate mechanical properties as an attractive solution for high-temperature power electronics packaging.
研究领域:
材料科学
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电子封装技术
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DOI
高影响因子
Membranes
·
2022
·Vol. 12
·期 4
·374
·
IF 4.562
Mingshu Wang,Chang Liu,Min Fan,Meiling Liu,Songtao Shen
Layer-by-layer (LBL) self-assembly technology has become a new research hotspot in the fabrication of nanofiltration membranes in recent years. However, there is a lack of a systematic approach for the assessment of influencing factors during the membrane fabrication process. In this study, the process optimization of LBL deposition was performed by a two-step statistical method. The multiple linear regression was performed on the results of single-factor experiments to determine the major influencing factors on membrane performance, including the concentration of Poly (allylamine hydrochloride) (PAH), glutaraldehyde, and the NaCl concentration in PAH solution. The Box–Behnken response surface method was then used to analyze the interactions between the selected factors, while their correlation with the membrane performance was obtained by polynomial fitting. The R2value of the regression models (0.97 and 0.94) was in good agreement with the adjusted R2value (0.93 and 0.86), indicating that the quadratic response models were adequate enough to predict the membrane performance. The optimal process parameters were finally determined through dual-response surface analysis to achieve both high membrane permeability of 14.3 LMH·MPa−1and MgSO4rejection rate of 90.22%.Keywords:layer-by-layer self-assembly;multiple regression analysis;nanofiltration membrane;process optimization;response surface methodology
研究领域:
材料科学
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环境工程
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DOI
PubMed
高影响因子
BIORESOURCE TECHNOLOGY
·
2022
·
IF 11.889
Xiaolan Li,Yufei Zhang,Hossain M. Zabed,Junhua Yun,Guoyan Zhang,Mei Zhao,Yuvaraj Ravikumar,Xianghui Qi
d -Arabitol is a top value-added compound with wide applications in the food, pharmaceutical and biochemical industries. Nevertheless, sustainable biosynthesis of d -arabitol is limited by lack of efficient strains and suitable fermentation process. Herein, metabolic engineering and process optimization were performed in Zygosaccharomyces rouxii to overcoming these limitations. Adopting systems metabolic engineering include enhancement of innate biosynthetic pathway, supply of precursor substrate d -ribulose-5P and cofactors regeneration, a novel recombinant strain ZR-5A with good performance was obtained, which boosted d -arabitol production up to 29.01 g/L, 59.31 % higher than the parent strain. Further with the optimum medium composition and fed-batch fermentation, the strain ZR-5A finally produced 149.10 g/L d -arabitol with the productivity of 1.04 g/L/h, which was the highest titer ever reported by Z.rouxii system. This is the first report on the use of metabolic engineering to construct Z. rouxii chassis for the sustainable production of d -arabitol.
研究领域:
生物技术
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代谢工程
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发酵技术
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生物化工
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PubMed
高影响因子
Chemical Engineering and Processing-Process Intensification
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2018
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IF 2.826
Wanru Wang,Weifeng Xu,Guilin Dai,Panliang Zhang,Kewen Tang
This paper studied the process optimization of reactive extraction of clorprenaline enantiomers (CP) by experiment and simulation. An efficient extraction system was obtained through single stage extraction experiments, where boric acid (BA) in aqueous phase and D -isobutyl tartrate (DT) in organic phase were selected as extractant and 1,2-dichlorethane was selected as organic solvent. The best enantioselectivity (α) with 2.012 was obtained. The extraction mechanism was proposed and thermodynamic constants such as physical partition coefficient and reactive equilibrium constants were obtained. Based on single stage extraction, phase and reactive equilibrium as well as the law of mass conservation, a model describing the fractional extraction process was acquired. The process of symmetrical separation of CP was optimized by the model. The optimal conditions including flow rate ratio (O/W) of 1.5, pH of 5.0, CH 3 COONa/CH 3 COOH solution of 0.1 mol/L, clorprenaline concentration of 5 mmol/L, BA concentration of 0.10 mol/L and DT concentration of 0.075 mol/L were obtained. Under this case, equal enantiomeric excess (ee eq ) could reach up to 67% by 10 stages. The simulated results revealed that the minimum series for ee eq > 97% and ee eq > 99% were 26 and 33, respectively. The results will provide guides for scale up and design.
研究领域:
化学工程
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制药工程
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高影响因子
CHINESE JOURNAL OF CHEMICAL ENGINEERING
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2024
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IF 3.7
Hai Cao,Hai-Bin Yang,Yanxiong Fang,Yuandi Zeng,Xiaolan Cai,Jingjing Ma
Daidzein has been widely used in pharmaceuticals, nutraceuticals, cosmetics, feed additives, etc. Its preparation process and related reaction mechanism need to be further investigated. A cost-effective process for synthesizing daidzein was developed in this work. In this paper, a two-step synthesis of daidzein (Friedel-Craft acylation and [5+1] cyclization) was developed via the employment of trifluoromethanesulfonic acid (TfOH) as an effective promoting reagent. The effect of reaction conditions such as solvent, the amount of TfOH, reaction temperature, and reactant ratio on the conversion rate and the yield of the reaction, respectively, was systematically investigated, and daidzein was obtained in 74.0% isolated yield under optimal conditions. Due to the facilitating effect of TfOH, the Friedel-Craft acylation was completed within 10 min at 90 °C and the [5+1] cyclization was completed within 180 min at 25 °C. In addition, a possible reaction mechanism for this process was proposed. The results of the study may provide useful guidance for industrial production of daidzein on a large scale.
研究领域:
制药
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营养补充品
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化妆品
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饲料添加剂
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有机化学
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工艺工程
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DOI
高影响因子
PROCESS SAFETY AND ENVIRONMENTAL PROTECTION
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2025
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IF 7.8
Juan Sun,Wenhui Zhang,Shuixiang Xie,Shuangxin Shi,Ziwei Du,Fang Liu,Qiyou Liu,Chunshuang Liu
Hydraulic fracturing produces complex organic wastewater, known as fracturing flowback fluid (FFF), which contains refractory pollutants and poses risks of secondary contamination, thereby challenging conventional treatment methods. This study developed an environmentally sustainable strategy using a microbial flocculant (MBF) synthesized from Bacillus paramycoides YQ1—a strain isolated from FFF—in combination with candelilla wax- modified fly ash cenospheres (CWFACs). Through process optimization, the MBF yield was increased from 4.38 to 5.78 g·L⁻¹ , and its flocculation efficiency improved from 60.06 % to 87.84 %. Under optimal conditions, MBF alone achieved removal rates of 86.67 % for chroma, 81.98 % for suspended solids (SS) removal, and 65.13 % for oil, along with effective degradation of polycyclic aromatic hydrocarbons (PAHs). The integrated MBF-CWFACs system demonstrated enhanced performance, attaining 88.50 % chroma removal, 96.29 % SS removal, and 95.30 % oil removal. Mechanistic analysis revealed synergistic effects between bioflocculation and adsorption processes. This integrated approach offers a sustainable solution for FFF treatment, addressing both process efficiency and environmental safety concerns, providing insights for developing eco-friendly wastewater treatment technologies in the petroleum industry.
研究领域:
环境工程
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微生物学
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水处理技术
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石油工业环境安全
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材料科学
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污染控制化学
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产品关联
DOI
高影响因子
Frontiers in Bioengineering and Biotechnology
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2025
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IF 4.8
Zhanjia Zhang
Introduction: Lactose intolerance affects 85%–95% of Chinese adults, creating substantial demand for low-lactose dairy products. This study aimed to develop a cost-effective β-galactosidase production process through solid-state fermentation (SSF) using agricultural byproducts.Methods: A high-yielding strain was isolated from Tibetan fermented yak milk and identified through morphological, biochemical, and 16S rDNA sequence analysis. Solid-state fermentation conditions were optimized using single-factor experiments and Box-Behnken response surface methodology. Enzymatic properties were characterized, and the enzyme was applied to milk lactose hydrolysis. Techno-economic and environmental impact analyses were conducted.Results: Lactobacillus plantarum LP-15 exhibited initial enzyme activity of 44.7 U/g. Optimal SSF conditions were determined as substrate ratio of wheat bran:soybean meal:whey powder (6:3:1), 37 °C, pH 6.5, and 55% moisture content, achieving enzyme activity of 186.3 U/g (4.17-fold improvement). The enzyme exhibited optimal activity at pH 6.5 and 42 °C, with Km of 2.8 mM and catalytic efficiency of 5.3 × 104 M−1s−1. Milk lactose was reduced by 81.9% within 4 h using 2.0 U/mL enzyme at 40 °C, meeting the low-lactose standard (≤0.1%). SSF reduced production costs by 35.7%, water usage by 94%, and CO2 emissions by 62.4% compared to liquid fermentation.Discussion: This study provides an economically viable and environmentally sustainable solution for low-lactose dairy production in China, establishing independent intellectual property rights while addressing nutritional needs of lactose-intolerant populations through circular utilization of agricultural by products.
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PubMed
高影响因子
Journal of Environmental Chemical Engineering
·
2025
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IF 7.2
Shuting Zhang,Jianwen Wei,Xuequan Zou,Linlin Geng,Xiaobin Zhou
This work demonstrates a strategic fabrication of high-performance CO 2 adsorbents by impregnating three conventional ionic liquids (ILs: [BMIM][NTf 2 ], [EMIM][NTf 2 ] or [EMIM][SCN]) with a covalent organic framework (COF) for carbon dioxide (CO 2 ) capture under simulated flue gas streams (1 bar, 15 vol% CO 2 , 60 ℃). Through the systematical assessment of the effects of IL structural features (different anions and cations), adding ratios (15–95 wt%), and operational temperatures (30–90 °C), it was shown that the adsorbent modified by [EMIM][SCN] in an appropriate amount (35 wt%) achieves the remarkable CO 2 adsorption capacity (5.273 mmol·g −1 at 60 ℃), representing a 3.7-fold enhancement compared to the original COF (1.419 mmol·g −1 ) due to its optimal combination of small molecular weight, short alkyl chain cation, and high CO 2 affinity anion. FTIR analysis revealed the potential adsorption mechanisms: the amine of COF chemisorbs CO 2 through carbamate formation, while the ILs enhance both chemisorption and physisorption of CO 2 via the thiocyanate nucleophilicity, the [NTf 2 ] - electronic redistribution, and hydrogen bonding of imidazolium, which is dominated by anion. The optimum CO 2 adsorption temperature (45–60 ℃) matches post-desulfurization flue gas conditions in coal-fired plants. With excellent performance and robust stability, these innovative adsorbents show practical potential for CO 2 capture in real post-combustion flue gas scenarios.
研究领域:
环境科学
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材料科学
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化学工程
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纳米技术
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DOI
高影响因子
Biotechnology for Biofuels and Bioproducts
·
2024
·Vol. 17
·期 1
·1-12
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IF 3.3
Zhang Bin,Gou Kexin,Xu Kexin,Li Zhimin,Guo Xiaoyan,Wu Xiaoyu
Background β-Arbutin, a hydroquinone glucoside found in pears, bearberry leaves, and various plants, exhibits antioxidant, anti-inflammatory, antimicrobial, and anticancer effects. β-Arbutin has wide applications in the pharmaceutical and cosmetic industries. However, the limited availability of high-performance strains limits the biobased production of β-arbutin. Results This study established the β-arbutin biosynthetic pathway in C. glutamicum ATCC13032 by introducing codon-optimized ubiC , MNX1 , and AS . Additionally, the production titer of β-arbutin was increased by further inactivation of csm and trpE to impede the competitive metabolic pathway. Further modification of the upstream metabolic pathway and supplementation of UDP-glucose resulted in the final engineered strain, C. glutamicum AR11, which achieved a β-arbutin production titer of 7.94 g/L in the optimized fermentation medium. Conclusions This study represents the first successful instance of de novo β-arbutin production in C. glutamicum , offering a chassis cell for β-arbutin biosynthesis.
研究领域:
生物技术
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代谢工程
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药学
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化妆品科学
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产品关联
DOI
PubMed
高影响因子
CERAMICS INTERNATIONAL
·
2025
·Vol. 51
·期 27
·54471-54479
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IF 5.6
He Chen,Lina Lv,Xiaoyu Li,Tingting Deng,Hao peng,Weicheng Xiang,Fangting Chi
Radioisotope thermoelectric generators (RTGs) produce electrical energy exclusively through the natural decay of radioactive materials, rendering them an ideal power source for space missions and other extreme environments. 241 Am is viewed as a promising substitute for 238 Pu as the heat-generating nuclide in these applications. However, there is currently no consensus on the sintering of 241 Am (Ⅲ) pellets. In this research, Nd (Ⅲ) oxide was used as a surrogate for americium (Ⅲ) oxide, and conventional cold-press-and-sinter methods were employed. Through a systematic investigation of the heating rate, holding time, and maximum temperature during the sintering of Nd (Ⅲ) oxide pellets made from commercial materials, an optimized sintering thermal cycle was developed. This curve enhances sintering efficiency and results in pellets with an open pore network, which is crucial for helium gas release. This work is significant in advancing the research and development of 241 Am nuclear batteries.
研究领域:
核化学
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材料科学
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能源工程
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空间电源技术
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固态离子学
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放射化学
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产品关联
DOI
高影响因子
Carbon Energy
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2025
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IF 24.2
Hong Liu,Kangyan Liu,Biao Zhang,Ziang Chen,Yi Yang,Qiang Sun,Tao Ye,Bed Poudel,Kai Wang,Congcong Wu
The key challenge in the preparation of perovskite solar cells is to enhance the reproducibility of PSC manufacturing, particularly by better controlling multiple high-dimensional process parameters. This study proposes a machine learning (ML) approach to efficiently predict and analyze perovskite film fabrication processes. By evaluating five classic ML algorithms on 130 experimental data sets from blade-coating parameters, the Random Forest (RF) model was identified as the most effective, enabling rapid prediction of over 100,000 parameter sets in just 10 min-equivalent to 3 years of manual experimentation. The RF model demonstrated strong predictive accuracy, with an R 2 close to 0.8. This approach led to the identification of optimal process parameter combinations, significantly improving the reproducibility of PSCs and reducing performance variance by approximately threefold, thereby advancing the development of scalable manufacturing processes.
研究领域:
材料科学
·
可再生能源
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机器学习应用
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薄膜技术
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）