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Ultrasonicwave-assisted tandem-reaction for synthesis of symmetrical vicinal diamines

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Chinese Chemical Letters 2007年第12期18卷 1469-1470页

作者： Gen Rong Qiang Xiang Mei Wu Qin wang Wen pei College of Chemical Engineering and Materials Zhejiang University of Technology Hangzhou 310014 China

A practical synthesis of symmetrical vicinal diamines with broad chemistry scope is described. The key step is the ultrasonicwave promoted tandem-reaction, two-step reaction sequence combining Mannich double condensations with benzo- triazole, glyoxal and primary or secondary amines and reduction of the bis（benzotriazole）-adducts with sodium borohydride proceeded smoothly in tetrahydrofuran in high yield at room temperature.

关键词： Vicinal diamine Benzotriazole Glyoxal Mannich reaction Synthesis

Control characteristics of D + A combined multi-pump controlled system

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High Technology Letters 2018年第3期24卷 303-312页

作者：姚静 wang pei Cao Xiaoming Zhang Yang Kong Xiangdong College of Mechanical Engineering Yanshan University The Laboratory of Heavy Machinery Fluid Power Transmission and Control in Hebei Yanshan University National and Local Joint Engineering Center for Advanced Forging Press Forming Technology and Equipment Faculty of Engineering Yanshan University

In order to solve the flow mismatch problem between pumping source output and workload demand,a novel configuration of D + A combined multi-pump controlled hydraulic system,similar to a pump-controlled system,is proposed for a large power hydraulic system in this study. This novel configuration consists of several parallel fixed displacement pumps of different sizes and proportional variable displacement pumps,which is controlled by digital signal( on/off) and analog signal respectively( D + A pumps). The system flow is divided into two parts,one is the total flow from fixed displacement pumps,and the other is the rest desired flow supplied by variable displacement pumps to smooth and improve the demand flow. First,basic design principles and evaluation indicators of the proposed system are introduced. Then,a flow state matrix of the binary-coding digital pumps( 1: 2: 4) is obtained to provide the control signals of pumps. Experimental results show that the system output flow tracks well with acceptable flow deviation,though a little lag behind input signal.

关键词： multi-pump design principles flow state matrix evaluation indicator energy saving

Effect of TiB_(2)Addition on Microstructure and Mechanical Properties of AA8009 Alloy Fabricated by Laser Additive Manufacturing

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 67-77页

作者： Xinxing Xiong Sijie Yu pei wang Junfang Qi Haichao Li Xulei wang Michael Ryan Debajyoti Bhaduri Rossitza Setchi Additive Manufacturing Institute Shenzhen UniversityShenzhen518060China Henan Key Laboratory of High Performance Carbon Fiber Reinforced Composites Institute of Carbon Matrix CompositesHenan Academy of SciencesZhengzhou450046China School of Materials Science and Engineering Shanghai University of Engineering ScienceShanghai201620China School of Materials Science and Engineering Zhengzhou University of AeronauticsZhengzhou450046China High-Value Manufacturing Research Group School of EngineeringCardiff UniversityCardiffCF243AAUK

The research involves the addition of 5 vol.%TiB_(2)particles into AA8009 alloy powder to synthesize TiB_(2)/AA8009 composite parts produced via laser powder bed fusion(LPBF).The addition of the TiB_(2)particles causes the TiB_(2)/AA8009 composites with and without annealing have lower compressive strength than AA8009 alloy due to the change of the strengthening *** results further indicated that solid solution strengthening was the main strengthening mechanism of the LPBF AA8009 alloy at room temperature whereas Orowan strengthening became the primary strengthening factor after annealing at 673 *** contrast,Orowan strengthening always remained the main strengthening mechanism for the TiB_(2)/AA8009 composite,irrespective of the annealing *** addition,after annealing of the LPBF parts at 673 K,the compressive yield strength(CYS)of the unblended AA8009 alloy specimens had a~2.5 times greater reduction(from 705±16 to 459±30 MPa)compared to that of the composite TiB_(2)/AA8009 samples(from 466±23 to 368±3 MPa).Therefore,TiB_(2)particles can suppress the drop in yield strength of LPBF AA8009 alloy below 673 K,providing a theoretical and experimental basis for the applications of both LPBF AA8009 and TiB_(2)/AA8009 alloys at low and medium temperatures.

关键词： Laser powder bed fusion AA8009 alloy Microstructure Mechanical properties

Serum thioredoxin activity:a promising biomarker for assessment of coronary stenosis severity in patients with coronary artery disease

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Science Bulletin 2017年第11期62卷 752-754页

作者： Jinling Li pei wang Li Xiao Jianmin Yu Xianrui Kong Liangwei Zhong Medical School University of Chinese Academy of Sciences Beijing Key Laboratory of Immunology Regulation and Organ Transplantation Basic Research Laboratory of Organ Transplant Institutethe 309th Hospital of the People's Liberation Army

Coronary artery disease(CAD)is one of the major death causes *** methods may improve the progress of ***,specific biomarkers are required for detecting coronary stenosis severity and monitoring *** spiral computed tom... 详细信息

关键词：动脉狭窄冠心病生物标记物蛋白活性冠状动脉造影冠状动脉疾病患者评价

Solar-assisted two-stage catalytic membrane reactor for coupling CO_(2) splitting with methane oxidation reaction

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Green Energy & Environment 2024年第11期9卷 1771-1780页

作者： Jinkun Tan Zhenbin Gu Zhengkun Liu pei wang Reinout Meijboom Guangru Zhang Wanqin Jin State Key Laboratory of Materials-Oriented Chemical Engineering College of Chemical EngineeringNanjing Tech University30 Puzhu Road(S)Nanjing211816China Quzhou Membrane Material Innovation Institute Nanjing Tech University QuzhouQuzhou324000China College of Energy and Electrical Engineering Hohai UniversityNanjing211106China Department of Chemical Sciences University of JohannesburgP.O.Box 524Auckland Park2600South Africa

A two-stage catalytic membrane reactor(CMR)that couples CO_(2) splitting with methane oxidation reactions was constructed based on an oxygen-permeable perovskite asymmetric *** asymmetric membrane comprises a dense SrFe_(0.9)Ta_(0.1)O_(3-σ)(SFT)separation layer and a porous Sr_(0.9)(Fe_(0.9)Ta_(0.1))_(0.9)Cu_(0.1)O_(3-σ)(SFTC)catalytic *** theﬁrst stage reactor,a CO_(2) splitting reaction(CDS:2CO_(2)→2CO+O_(2))occurs at the SFTC catalytic ***,the O_(2) product is selectively extracted through the SFT separation layer to the permeated side for the methane combustion reaction(MCR),which provides an extremely low oxygen partial pressure to enhance the oxygen *** the second stage,a Sr_(0.9)(Fe_(0.9)Ta_(0.1))_(0.9)Ni_(0.1)O_(3-σ)(SFTN)catalyst is employed to reform the products derived from *** two-stage CMR design results in a remarkable 35.4%CO_(2) conversion for CDS at 900℃.The two-stage CMR was extended to a hollowﬁber conﬁguration combining with solar *** solar-assisted two-stage CMR can operate stably for over 50 h with a high hydrogen yield of 18.1 mL min^(-1) cm^(-2).These results provide a novel strategy for reducing CO_(2) emissions,suggesting potential avenues for the design of the high-performance CMRs and catalysts based on perovskite oxides in the future.

关键词： CO_(2)splitting Two-stage catalytic membrane reactor Perovskite oxide Asymmetric membrane Solar irradiation assisted

Screening of glucosinolates degrading lactic acid bacteria and their utilization in rapeseed meal fermentation

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Grain & Oil Science and Technology 2024年第3期7卷 168-176页

作者： Yifang Chen Chong Xie Muhammad Bilal pei wang Runqiang Yang College of Food Science and Technology Whole Grain Food Engineering Research CenterNanjing Agricultural UniversityNanjing 210095JiangsuChina The Sanya Institute of Nanjing Agricultural University Sanya 572024HainanChina National Technique Innovation Center for Regional Wheat Production/Key Laboratory of Crop Physiology Ecologyand ManagementMinistry of Agriculture/National Engineering and Technology Center for Information AgricultureNanjing Agricultural UniversityNanjing 210095JiangsuChina

Rapeseed meal is a promising food ingredient, but its utilization is limited by the presence of some potentially harmful ingredients, such as glucosinolates. Fermentation is a cost-effective method of detoxication but a food-grade starter culture with glucosinolates degradation capacity is required. In this study, 46 strains of lactic acid bacteria from traditional paocai brines were screened for their ability to glucosinolate degradation. The results showed that more than 50% of the strains significantly degraded glucosinolates. Two strains of Lactiplantibacillus(p7 and s7) with high capacity of glucosinolates degradation through producing enzymes were identified. Then,an optimized condition for rapeseed meal fermentation by p7 was established to degrade glucosinolates, which can achieve about 80% degradation. UPLC/Q-TOF-MS analysis showed that the degradation rate of individual glucosinolates was different and the degradation rate of gluconapin and progoitrin in rapeseed meal can reach more than 90%. Meanwhile, fermentation with p7 can improve safety of rapeseed meal by inhibiting the growth of Enterobacteriaceae and improve its nutritional properties by degrading phytic acid. The in vitro digestion experiments showed that the content of glucosinolates in rapeseed meal decreased significantly during gastric digestion. Meanwhile, fermentation with p7 can greatly improve the release of soluble protein and increase the contents of free essential amino acids, such as lysine(increased by 12 folds) and methionine(increased by 10 folds).

关键词： Rapeseed meal Glucosinolates Fermentation Lactic acid bacteria In vitro digestion

Temporal assembly patterns of microbial communities in three parallel bioreactors treating low-concentration coking wastewater with differing carbon source concentrations

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Journal of Environmental Sciences 2024年第3期137卷 455-468页

作者： Weijia Li Yu Xia Na Li Jie Chang Jing Liu pei wang Xuwen He School of Chemical and Environmental Engineering China University of Mining and Technology-BeijingBeijing 100083China

Carbon source is an important factor of biological treatment systems, the effects of which on their temporal community assembly patterns are not sufficiently understood *** this study, the temporal dynamics and driving mechanisms of the communities in three parallel bioreactors for low-concentration coking wastewater(CWW) treatment with differing carbon source concentrations(S0 with no glucose addition, S1 with 200 mg/L glucose addition and S2 with 400 mg/L glucose addition) were comprehensively studied. Highthroughput sequencing and bioinformatics analyses including network analysis and Infer Community Assembly Mechanisms by Phylogenetic bin-based null model(iCAMP) were used. The communities of three systems showed turnover rates of 0.0029~0.0034 every 15days. Network analysis results showed that the S0 network showed higher positive correlation proportion(71.43%) and clustering coefficient(0.33), suggesting that carbon source shortage in S0 promoted interactions and cooperation of microbes. The neutral community model analysis showed that the immigration rate increased from 0.5247 in S0 to 0.6478in S2. The iCAMP analysis results showed that drift(45.89%) and homogeneous selection(31.68%) dominated in driving the assembly of all the investigated microbial *** contribution of homogeneous selection increased with the increase of carbon source concentrations, from 27.92% in S0 to 36.08% in S2. The OTUs participating in aerobic respiration and tricarboxylic acid(TCA) cycle were abundant among the bins mainly affected by deterministic processes, while those related to the metabolism of refractory organic pollutants in CWW such as alkanes, benzenes and phenols were abundant in the bins dominated by stochastic processes.

关键词： Coking wastewater treatment Temporal dynamics Network analysis Deterministic processes Stochastic processes

Numerical Simulations of Magnetic Reconnection in an Asymmetric Current Sheet

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Chinese Physics Letters 2013年第12期30卷 79-82页

作者： wang pei-Ran HUANG Can LU Quan-Ming wang Rong-Sheng wang Shui CAS Key Laboratory of Geospace Environment Department of Geophysics and Planetary ScienceUniversity of Science and Technology of ChinaHefei 230026 Institute of Geology and Geophysics Chinese Academy of SciencesBeijing 100029

Previous particle-in-cell simulations have shown that electron phase-space holes(electron holes),where the associated parallel electric field has a bipolar structure,exist near the four separatrices in anti-parallel magnetic *** performing two-dimensional(2-D)particle-in-cell(PIC)simulations,here we investigate magnetic reconnection in an asymmetric current sheet,with emphasis on the parallel electric field near the *** with magnetic reconnection in a symmetric current sheet,it is found that the parallel electric field with a bipolar structure only exists around the separatrices in the upper region with a lower density(upper separatrices).Such a bipolar structure of the parallel electric field is considered to be associated with electron holes resulting from the nonlinear evolution of the electron beam instability excited by the high-speed electron flow formed after their acceleration around the X *** disappearance of the parallel electric field around the separatrices in the lower region with a higher density(lower separatrices)may be due to the transverse instability,which is unstable in a weak magnetized plasma.

关键词： reconnection structure field

COMPOSITE MODELING APPROACH AND EXPERIMENTAL STUDY FOR SUBSURFACE TRANSPORT OF CONTAMINANTS FROM LAND-DISPOSAL SITES

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Journal of Hydrodynamics 2003年第4期15卷 1-9页

作者： wang Chao, wang pei-fang, Li Yong Department of Environmental Engineering, Hohai University, Nanjing 210098, China Dept. of Environ. Eng. Hohai Univ. Nanjing 210098 China

A composite modeling approach was presented for simulating thethree-dimensional (3-D) subsurface transport of dissolved contaminants with transformation *** approach was based on vertical infiltration and contaminant transport in the unsaturated zoneand 3-D groundwater flow and contaminant migration in the saturated zone. Moisture movement andgroundwater flow were considered to be steady, but contaminant transport was treated as continuousand transient. The transformed unsaturated zone and saturated zone transport equations were solvednumerically with different techniques. The model contains a 3-D solution to flow and transport inthe saturated zone, as well as two-dimensional solutions to vertical cross-sectional and arealscenarios. In order to verify the composite modeling, extensive experiments were conducted in twolarge-scale variable-slope soil tanks of 1200cm in length, 150cm in width and 150cm in height. Sandsoil was filled in the tank as the porous media. The solutions of KBr or NH_4C1 were introduced intoeach soil tank from 80 X 37cm^2 area sources located on the top of the porous medium. Results fromnumerical simulations were compared with the data from tests. Predicted results are in goodagreement with the experimental data.

关键词： composite modeling groundater flow finite element model experiment