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FBRM and PVM investigations of the double feed semi-batch crystallization of 6-aminopenicillanic acid

Min SU, Lin WANG, Hua SUN, Jingkang WANG

《化学科学与工程前沿（英文）》 2009年 第3卷 第3期   页码 282-288 doi: 10.1007/s11705-009-0018-7

摘要： 6-Aminopenicillanic acid (6-APA) is a crucial pharmaceutical intermediate in the chemistry of semi-synthetic antibiotics. The focused beam reflectance measurement (FBRM) technology and particle vision measurement (PVM) technology were employed to the processes of online-monitoring of 6-APA crystallization behavior in a double-feeding semi-batch crystallizer. Experiments were carried out with four kinds of double-feeding policies and the results were compared with the traditional single-feeding. Records and analysis of FBRM indicated that the nucleation of double feeding policy was much higher than single policy, and chord length of 6-APA was almost determined and had little change after the nucleation peak. Ostwald ripening process had no significant effect on further growth of 6-APA crystal. PVM images showed that the crystal habit of 6-APA was continuously changed during the crystallization process. The development of (002) face in the final crystal for the five feeding policies were different.

关键词： 6-aminopenicillanic acid     crystallization     double-feeding     FBRM     PVM     crystal habit    

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Influence of glucose feeding on the ligninolytic enzyme production of the white-rot fungus Phanerochaete

ZHOU Xiaoyan, WEN Xianghua, FENG Yan

《环境科学与工程前沿（英文）》 2007年 第1卷 第1期   页码 89-94 doi: 10.1007/s11783-007-0017-1

摘要： The present work studied the influence of glucose feeding on the ligninolytic enzyme production of in a nitrogen-limited (C/N ratio is 56/8.8 mmol/L) medium. Several sets of shaking flask experiments were conducted. The results showed that 2 g/L glucose feeding on the first day of the culture (24 h after the inoculation) stimulated both fungal biomass growth and enzyme production. The manganese peroxidase (MnP) activity was 2.5 times greater than that produced in cultures without glucose feeding. Furthermore, the glucose feeding mode in fed-batch culture was also investigated. Compared to cultures with glucose feeding every 48 h, cultures with glucose feeding of 1.5 g/L (final concentration) every 24 h produced more enzymes. The peak and total yield of MnP activity were 2.7 and 3 times greater compared to the contrast culture, respectively, and the enzyme was kept stable for 4 days with an activity of over 200 U/L.

关键词： enzyme production     fed-batch culture     nitrogen-limited     inoculation     mmol/L    

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Sustainable intensification of agriculture is key to feeding Africa in the 21st century

Shenggen FAN

《农业科学与工程前沿（英文）》 2020年 第7卷 第4期   页码 366-370 doi: 10.15302/J-FASE-2020342

摘要：

Africa in facing numerous challenges in the 21st century in feeding its rapidly increasing population. Land resources have become limited due to urbanization and industrialization. The existing agricultural land has been degraded and soil fertility has declined due to unsustainable farming practices. Despite of progress made in the past several decades, hunger and malnutrition in Africa still hinder health, human development and economic growth, which will become even worse in the future if proper measures are not taken. Sustainable intensification is the only solution to tackling both environmental sustainability including climate change and malnutrition, i.e., to produce more foods in terms of nutrients human body needs with less natural resources and carbon emissions. To achieve this vision, innovations in technologies, policies and institutions are essential. The Chinese experience in Agricultural Green Development (AGD) can be shared with Africans when the region is pursuing its sustainable intensification strategy.

关键词： Africa     sustainable intensification     Agricultural Green Development     climate change     malnutrition    

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Experimental measurement of double-K fracture parameters of concrete with small-size aggregates

ZHANG Xiufang, XU Shilang, ZHENG Shuang

《结构与土木工程前沿（英文）》 2007年 第1卷 第4期   页码 448-457 doi: 10.1007/s11709-007-0061-8

摘要： The double- fracture model can well describe the development of cracks undergoing during the entire fracture process in concrete. Therefore, it has been selected as the theoretical basis of the Norm for fracture test of

关键词： development     concrete     theoretical     double- fracture    

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以喂养方式视角浅析新时期城市基层计生优质服务

严小青

《中国工程科学》 2014年 第16卷 第5期   页码 24-30

摘要：

通过选取杭州市上城区社区卫生院109 例婴儿及其母亲为调查对象，利用SPSS18.0 软件分别从一般参考量、影响喂养方式相关性因素以及基层计生优质服务需求进行数据统计分析，从而得到影响母乳喂养因素、喂养方式与婴儿体格关系以及服务需求重点，从而提出要从卫生计生联手、育医结合，立足基层架构群众满意服务网络；探索途径、优化服务，实现流动人口优质服务一盘棋；强化队伍、创新机制，探索建立科学规范服务考核评估体系三方面全面提升新时期基层计生优质服务水平。

关键词： 喂养方式     统计分析     计生优质服务    

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Postnatal feeding with high-fat diet induces obesity and precocious puberty in C57BL/6J mouse pups: a

null

《医学前沿（英文）》 2017年 第11卷 第2期   页码 266-276 doi: 10.1007/s11684-017-0530-y

摘要：

Childhood obesity and obesity-related metabolic complications are induced by a high-fat postnatal diet. The lack of a suitable animal model, however, remains a considerable challenge in obesity studies. In the current study, we provided high-fat diet (HFD) to dams during lactation and to pups after weaning. We also developed a novel model of C57BL/6J mouse pups with HFD-induced postnatal obesity. Results showed that feeding with HFD induces fat deposition and obesity in pups. Furthermore, HFD more potently increased the body weight (BW) of male than female pups. HFD-fed female pups were obese, underwent precocious puberty, and showed increased kisspeptin expression in the hypothalamus. However, parental obesity and precocious puberty exerted no synergistic effects on the HFD-induced postnatal weight gain and puberty onset of the pups. Interestingly, some HFD-fed litters with normal BW also exhibited precocious puberty. This finding suggested that diet composition but not BW triggers puberty onset. Our model suggests good construction validity of obesity and precocious puberty. Furthermore, our model can also be used to explore the mutual interactions between diet–induced postnatal childhood obesity and puberty.

关键词： postnatal HFD feeding     obesity     kisspeptin     HPG axis     precocious puberty    

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Numerical study of thermal characteristics of double skin facade system with middle shade

Shaoning LIU, Xiangfei KONG, Hua YANG, Minchao FAN, Xin ZHAN

《能源前沿（英文）》 2021年 第15卷 第1期   页码 222-234 doi: 10.1007/s11708-017-0480-8

摘要： Architectural shade is an effective method for improving building energy efficiency. A new shade combined with the double skin façade (DSF) system, called middle shade (MS), was introduced and developed for buildings. In this paper, a 3D dynamic simulation was conducted to analyze the influence of MS combined with DSF on the indoor thermal characteristics. The research on MS for DSF involves the temperature, the ventilation rate, the velocity distribution of the air flow duct, and the indoor temperature. The results show that the angle and position of the shade in the three seasons are different, and different conditions effectively enhance the indoor thermal characteristics. In summer, the appearance of MS in DSF makes the indoor temperature significantly lower. The indoor temperature is obviously lower than that of the air flow duct, and the temperature of the air flow duct is less affected by MS. The influence of the position of blinds on indoor temperature and ventilation rate is greater than the influence of the angle of blinds. According to the climate characteristics of winter and transition season, in winter, early spring, and late autumn, the indoor temperature decreases with the increase of the position of blinds at daytime, but the opposite is true at night. The results found in this paper can provide reference for the design and use of MS combined with DSF in hot summer and cold winter zone.

关键词： middle shade     position     thermal characteristics     double skin facade    

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Moment-curvature relationship of FRP-concrete-steel double-skin tubular members

Mingxue LIU, Jiaru QIAN

《结构与土木工程前沿（英文）》 2009年 第3卷 第1期   页码 25-31 doi: 10.1007/s11709-009-0012-7

摘要： Tests were conducted on 3 specimens to study the flexural behavior of fiber reinforced polymer (FRP)-concrete-steel double-skin tubular members (DSTMs). The strip method was used to calculate the section moment-curvature curves of the 3 specimens and 12 models. A theoretical formula is presented for the flexural strength of DSTMs. The test results show that the tension zone of the specimen FRP tubes was in hoop compression while the compression zone was in hoop tension. The load-carrying capacity did not decrease even when the mid-span deflection reached about 1/24 of the span length. The tests, simulation and theoretical analysis resulted in a simplified formula for the flexural strength of DSTMs and a tri-linear moment-curvature model was expressed as a function of the section bending stiffness for DSTMs.

关键词： fiber reinforced polymer (FRP)     concrete     steel     double-skin tubular members (DSTMs)     moment-curvature curve     flexural strength    

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Enhancement of distillate output of double basin solar still with vacuum tubes

Hitesh N PANCHAL, P K SHAH

《能源前沿（英文）》 2014年 第8卷 第1期   页码 101-109 doi: 10.1007/s11708-014-0299-5

摘要： The latent heat of condensation is lost to the atmosphere; hence it is not utilized to increase distillate output of single basin solar stills. This difficulty was overcome by attaching an additional basin to the main basin. The performance of the double basin solar still was also increased by attaching vacuum tubes to the lower basin; hence the lower basin possessed a higher temperature throughout the day. The latent heat of condensation of the bottom basin was also utilized to increase distillate. But the distillate output of the top basin was even lower compared with that of the bottom basin. This paper proposed a novel approach to increase the distillate output of the double basin solar still attached with vacuum tubes by introducing different sensible energy storage materials like pebbles, black granite gravel and calcium stones to increase the basin area. Experiments were conducted in climate conditions of Mehsana (23.6000° N, 72.4000° E) Gujarat from April to September 2013 with a constant water depth of 2 cm in the top basin with and without the use of basin materials. The results showed that the distillate output of basin material with calcium stones is greater (74%) compared with that of black granite gravel and pebbles. The integration of vacuum tubes with solar still greatly increases the distillate output of the solar still by providing hot water at the lower basin.

关键词： double basin solar still     calcium stones     pebbles     granite gravel     distillate output    

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Latest development of double perovskite electrode materials for solid oxide fuel cells: a review

Shammya AFROZE, AfizulHakem KARIM, Quentin CHEOK, Sten ERIKSSON, Abul K. AZAD

《能源前沿（英文）》 2019年 第13卷 第4期   页码 770-797 doi: 10.1007/s11708-019-0651-x

摘要： Recently, the development and fabrication of electrode component of the solid oxide fuel cell (SOFC) have gained a significant importance, especially after the advent of electrode supported SOFCs. The function of the electrode involves the facilitation of fuel gas diffusion, oxidation of the fuel, transport of electrons, and transport of the byproduct of the electrochemical reaction. Impressive progress has been made in the development of alternative electrode materials with mixed conducting properties and a few of the other composite cermets. During the operation of a SOFC, it is necessary to avoid carburization and sulfidation problems. The present review focuses on the various aspects pertaining to a potential electrode material, the double perovskite, as an anode and cathode in the SOFC. More than 150 SOFCs electrode compositions which had been investigated in the literature have been analyzed. An evaluation has been performed in terms of phase, structure, diffraction pattern, electrical conductivity, and power density. Various methods adopted to determine the quality of electrode component have been provided in detail. This review comprises the literature values to suggest possible direction for future research.

关键词： double perovskites     electrode materials     hydrocarbon fuel     solid oxide fuel cells    

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Nanosilver anchored alginate/poly(acrylic acid/acrylamide) double-network hydrogel composites for efficient

《化学科学与工程前沿（英文）》 2023年 第17卷 第7期   页码 893-905 doi: 10.1007/s11705-022-2290-8

摘要： A novel alginate/poly(acrylic acid/acrylamide) double-network hydrogel composite with silver nanoparticles was successfully fabricated using the sol–gel method. The presence of carboxyl and amide groups in the network structure provided abundant active sites for complexing silver ions, facilitating the in situ reduction and confinement of silver nanoparticles. In batch experiments, the optimal silver loading was 20%, and 5 mmol·L–1 of p-nitrophenol was completely degraded in 113 s with a rate constant value of 4.057 × 10−2 s–1. In the tap water system and simulated seawater system, the degradation time of p-nitrophenol at the same concentration was 261 and 276 s, respectively, with a conversion rate above 99%. In the fixed-bed experiment, the conversion rate remained above 74% after 3 h at a flowing rate of 7 mL·min–1. After 8 cycling tests, the conversion rate remained at 98.7%. Moreover, the catalyst exhibited outstanding performance in the degradation experiment of four typical organic dyes.

关键词： double-network hydrogel     dye degradation     silver nanoparticles     alginate    

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Synergistic effect of V and Fe in Ni/Fe/V ternary layered double hydroxides for efficient and durable

《化学科学与工程前沿（英文）》 2023年 第17卷 第1期   页码 102-115 doi: 10.1007/s11705-022-2179-6

摘要： High-performance and stable electrocatalysts are vital for the oxygen evolution reaction (OER). Herein, via a one-pot hydrothermal method, Ni/Fe/V ternary layered double hydroxides (NiFeV-LDH) derived from Ni foam are fabricated to work as highly active and durable electrocatalysts for OER. By changing the feeding ratio of Fe and V salts, the prepared ternary hydroxides were optimized. At an Fe:V ratio of 0.5:0.5, NiFeV-LDH exhibits outstanding OER activity superior to that of the binary hydroxides, requiring overpotentials of 269 and 274 mV at 50 mA·cm–2 in the linear sweep voltammetry and sampled current voltammetry measurements, respectively. Importantly, NiFeV-LDH shows extraordinary long-term stability (≥ 75 h) at an extremely high current density of 200 mA·cm–2. In contrast, the binary hydroxides present quick decay at 200 mA·cm–2 or even reduced current densities (150 and 100 mA·cm–2). The outstanding OER performance of NiFeV-LDH benefits from the synergistic effect of V and Fe while doping the third metal into bimetallic hydroxide layers: (a) Fe plays a crucial role as the active site; (b) electron-withdrawing V stabilizes the high valence state of Fe, thus accelerating the OER process; (c) V further offers great stabilization for the formed intermediate of FeOOH, thus achieving superior durability.

关键词： oxygen evolution reaction     electrocatalysts     ternary layered double hydroxides     long-term stability    

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HEMIPTERAN-TRANSMITTED PLANT VIRUSES: RESEARCH PROGRESS AND CONTROL STRATEGIES

《农业科学与工程前沿（英文）》 2022年 第9卷 第1期   页码 98-109 doi: 10.15302/J-FASE-2021389

摘要：

About 80% of plant viruses are transmitted by specific insect vectors, especially hemipterans with piercing-sucking mouthparts. Many virus-transmitting insects are also important crop pests that cause considerable losses in crop production. This review summarizes the latest research findings on the interactions between plant viruses and insect vectors and analyzes the key factors affecting insect transmission of plant viruses from the perspectives of insect immunity, insect feeding, and insect symbiotic microorganisms. Additionally, by referring to the latest applications for blocking the transmission of animal viruses, potential control strategies to prevent the transmission of insect-vectored plant viruses using RNAi technology, gene editing technology, and CRISPR/Cas9+ gene-driven technology are discussed.

 

关键词： control strategies / feeding / immunity / insect vector / microorganism / plant virus    

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Prediction and cause investigation of ozone based on a double-stage attention mechanism recurrent neural

《环境科学与工程前沿（英文）》 2023年 第17卷 第2期 doi: 10.1007/s11783-023-1621-4

摘要：

● Used a double-stage attention mechanism model to predict ozone.

关键词： Ozone prediction     Deep learning     Time series     Attention     Volatile organic compounds    

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Hierarchically porous cellulose nanofibril aerogel decorated with polypyrrole and nickel-cobalt layered double

《化学科学与工程前沿（英文）》 2023年 第17卷 第10期   页码 1593-1607 doi: 10.1007/s11705-023-2348-2

摘要： With increasing emphasis on green chemistry, biomass-based materials have attracted increased attention regarding the development of highly efficient functional materials. Herein, a new pore-rich cellulose nanofibril aerogel is utilized as a substrate to integrate highly conductive polypyrrole and active nanoflower-like nickel-cobalt layered double hydroxide through in situ chemical polymerization and electrodeposition. This ternary composite can act as an effective self-supported electrode for the electrocatalytic oxidation of glucose. With the synergistic effect of three heterogeneous components, the electrode achieves outstanding glucose sensing performance, including a high sensitivity (851.4 µA·mmol−1·L·cm−2), a short response time (2.2 s), a wide linear range (two stages: 0.001−8.145 and 8.145−35.500 mmol·L−1), strong immunity to interference, outstanding intraelectrode and interelectrode reproducibility, a favorable toxicity resistance (Cl‒), and a good long-term stability (maintaining 86.0% of the original value after 30 d). These data are superior to those of some traditional glucose sensors using nonbiomass substrates. When determining the blood glucose level of a human serum, this electrode realizes a high recovery rate of 97.07%–98.89%, validating the potential for high-performance blood glucose sensing.

关键词： cellulose nanofibril     aerogel     nickel-cobalt layered double hydroxide     polypyrrole     nonenzymatic glucose sensor    

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标题 作者 时间 类型 操作

FBRM and PVM investigations of the double feed semi-batch crystallization of 6-aminopenicillanic acid

Min SU, Lin WANG, Hua SUN, Jingkang WANG

期刊论文

Influence of glucose feeding on the ligninolytic enzyme production of the white-rot fungus Phanerochaete

ZHOU Xiaoyan, WEN Xianghua, FENG Yan

期刊论文

Sustainable intensification of agriculture is key to feeding Africa in the 21st century

Shenggen FAN

期刊论文

Experimental measurement of double-K fracture parameters of concrete with small-size aggregates

ZHANG Xiufang, XU Shilang, ZHENG Shuang

期刊论文

以喂养方式视角浅析新时期城市基层计生优质服务

严小青

期刊论文

Postnatal feeding with high-fat diet induces obesity and precocious puberty in C57BL/6J mouse pups: a

null

期刊论文

Numerical study of thermal characteristics of double skin facade system with middle shade

Shaoning LIU, Xiangfei KONG, Hua YANG, Minchao FAN, Xin ZHAN

期刊论文

Moment-curvature relationship of FRP-concrete-steel double-skin tubular members

Mingxue LIU, Jiaru QIAN

期刊论文

Enhancement of distillate output of double basin solar still with vacuum tubes

Hitesh N PANCHAL, P K SHAH

期刊论文

Latest development of double perovskite electrode materials for solid oxide fuel cells: a review

Shammya AFROZE, AfizulHakem KARIM, Quentin CHEOK, Sten ERIKSSON, Abul K. AZAD

期刊论文

Nanosilver anchored alginate/poly(acrylic acid/acrylamide) double-network hydrogel composites for efficient

期刊论文

Synergistic effect of V and Fe in Ni/Fe/V ternary layered double hydroxides for efficient and durable

期刊论文

HEMIPTERAN-TRANSMITTED PLANT VIRUSES: RESEARCH PROGRESS AND CONTROL STRATEGIES

期刊论文

Prediction and cause investigation of ozone based on a double-stage attention mechanism recurrent neural

期刊论文

Hierarchically porous cellulose nanofibril aerogel decorated with polypyrrole and nickel-cobalt layered double

期刊论文