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Investigation on Reduction of Pressure Fluctuation for a Double-Suction Centrifugal Pump

Chinese Journal of Mechanical Engineering 2021年第1期34卷 181-198页

作者： Qianqian li shiyang li Peng Wu Bin Huang Dazhuan Wu College of Energy Engineering Zhejiang UniversityHangzhou 310058China Zhejiang Zhixin Technology Co. LtdShaoxing 312000China Ocean College Zhejiang UniversityZhoushan 310021China The State Key Laboratory of Fluid Power Tran smission and Control Hangzhou 310058China

Double-suction centrifugal pumps have been applied extensively in many areas,and the significance of pressure fluctuations inside these pumps with large power is becoming increasingly *** this study,a double-suction centrifugal pump with a high-demand for vibration and noise was redesigned by increasing the flow uniformity at the impeller discharge,implemented by combinations of more than two ***,increasing the number of the impeller blades was intended to enhance the bounding effect that the blades imposed on the ***,increasing the radial gap between the impeller and volute was applied to reduce the rotor-stator ***,the staggered arrangement was optimized to weaken the efficacy of the interference *** on numerical simulation,the steady and unsteady characteristics of the pump models were *** the fluctuation analysis in the frequency domain,the dimensionless pressure fluctuation amplitude at the blade passing frequency and its harmonics,located on the monitoring points in the redesigned pumps(both with larger radial gap),are reduced a ***,in the volute of the model with new impellers staggered at 12°,the average value for the dimensionless pressure fluctuation amplitude decreases to 6%of that in prototype *** dimensionless rootmean-square pressure contour on the mid-span of the impeller tends to be more uniform in the redesigned models(both with larger radial gap);similarly,the pressure contour on the mid-section of the volute presents good uniformity in these models,which in turn demonstrating a reduction in the pressure fluctuation *** results reveal the mechanism of pressure fluctuation reduction in a double-suction centrifugal pump,and the results of this study could provide a reference for pressure fluctuation reduction and vibration performance reinforcement of doublesuction centrifugal pumps and other pumps.

关键词： Double-suction centrifugal pump Pressure fluctuation Flow uniformity Numerical simulation

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Extraction of Natural Nanostructured Hydroxyapatite from Pacific Cod(Gadus macrocephalus)Bone with a Thermostable Collagenolytic Protease and Its ex vivo Intestinal Bioavailability

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Journal of Ocean University of China 2023年第6期22卷 1613-1620页

作者： GUO Wei li shiyang JING Zhehua WU Haohao School of Pharmacy Binzhou Medical UniversityYantai 264003China College of Food Science and Engineering Ocean University of ChinaQingdao 266003China

Natural nano-hydroxyapatite(HA)was extracted from Pacific cod(Gadus macrocephalus)bone with a thermostable col-lagenolytic protease in the present *** for the enzymatic reaction were optimized to be 60℃and pH 7.0,and a desir-able extraction efficiency was achieved by using the crude collagenolytic *** light scattering,transmission electron microscopy and energy-dispersive X-ray analysis revealed that nano-HA are anionic spherical(about 110nm)particles mainly com-prised of calcium and phosphorus at an approximate ratio of 5:*** evaluated with the mouse ex vivo intestinal segments,the extracted nano-HA displayed comparable level of intestinal bioavailability to the positive control CaCl_(2).By treating with inhibitors(NaN3,ami-loride)and low temperature(4℃),clathrin-mediated endocytosis was assumed to involve the intestinal absorption of ***-all,the application of thermostable collagenolytic protease is proved to be a promising alternative method for nano-HA extraction from natural resource with improved ecological and biological value.

关键词： nano-hydroxyapatite thermostable collagenolytic protease Pacific cod(Gadus macrocephalus)bone intestinal bio-availability

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Can arbuscular mycorrhiza and fertilizer management reduce phosphorus runoff from paddy fields?

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Journal of Environmental Sciences 2015年第7期27卷 211-218页

作者： Shujuan Zhang li Wang Fang Ma Xue Zhang Zhe li shiyang li Xiaofeng Jiang State Key Laboratory of Urban Water Resource and Environment School of Municipal and Environmental EngineeringHarbin Institute of Technology

Our study sought to assess how much phosphorus（P） runoff from paddy fields could be cut down by fertilizer management and inoculation with arbuscular mycorrhizal fungi. A field experiment was conducted in Lalin River basin, in the northeast China： six nitrogen-phosphorus-potassium fertilizer levels were provided（0, 20%, 40%, 60%, 80%, and 100% of the recommended fertilizer supply）, with or without inoculation with Glomus mosseae. The volume and concentrations of particle P（PP） and dissolved P（DP） were measured for each runoff during the rice growing season. It was found that the seasonal P runoff, including DP and PP, under the local fertilization was 3.7 kg/ha, with PP, rather than DP, being the main form of P in runoff water. Additionally, the seasonal P runoff dropped only by 8.9% when fertilization decreased by 20%; rice yields decreased with declining fertilization. We also found that inoculation increased rice yields and decreased P runoff at each fertilizer level and these effects were lower under higher fertilization. Conclusively, while rice yields were guaranteed arbuscular mycorrhizal inoculation and fertilizer management would play a key role in reducing P runoff from paddy fields.

关键词： Arbuscular mycorrhizal fungi Fertilizer Paddy fields Phosphorus runoff Rice

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Coupling magnetic particles with flocculants to enhance demulsification and separation of waste cutting emulsion for engineering applications

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Journal of Environmental Sciences 2021年第7期33卷 173-183页

作者： Yongjiao Xiong Baoqiang Wu Xiangfeng Huang Chenlu li Bin Lu Jia liu lijun Lu shiyang li Kaiming Peng College of Environmental Science and Engineering State Key Laboratory of Pollution Control and Resource ReuseMinistry of Education Key Laboratory of Yangtze River Water EnvironmentShanghai Institute of Pollution Control and Ecological SecurityTongji UniversityShanghai 200092China

Magnetic particles were coupled with a flocculant to enhance the demulsification and separation of waste cutting *** optimal magnetic particle size and critical magnetic field conditions were investigated to achieve large-scale engineering application of magnetic demulsification separation for waste cutting emulsion *** micro-scale magnetic particles were found to show comparable effects to nano-scale magnetic particles on enhancing the demulsification and separation of cutting emulsions,which are beneficial for broadening the selectivity of low-cost magnetic *** critical magnetic separation region was determined to be an area 40 mm from the magnetic field *** to the flocculant demulsification,the magnetic demulsification separation exhibited a significant advantage in accelerating flocs-water separation by decreasing the separation time of flocs from 180-240 min to less than 15 min,compressing the flocs by reducing the floc volume ratio from 60%-90%to lower than 20%,and showing excellent adaptability to the variable properties of waste cutting *** with the design of the magnetic disk separator,continuous demulsification separation of the waste cutting emulsion was achieved at 1.0 t/hr for at least 10 hr to obtain clear effluent with 81%chemical oxygen demand removal and 89%turbidity *** study demonstrates the feasibility of applying magnetic demulsification separation to large-scale continuous treatment of waste ***,it addresses the flocs-water separation problems that occur in practical flocculant demulsification engineering applications.

关键词： Waste cutting emulsion Magnetic particles Demulsification and separation Magnetic disk separator Large-scale treatment

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LARGE-SCALE FARMING BENEFITS SOIL ACIDIFICATION ALLEVIATION THROUGH IMPROVED FIELD MANAGEMENT IN BANANA PLANTATIONS

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Frontiers of Agricultural Science and Engineering 2023年第1期10卷 48-60页

作者： Donghao XU Jiangzhou ZHANG Yajuan li shiyang li Siyang REN Yuan FENG Qichao ZHU Fusuo ZHANG College of Resources and Environmental Sciences China Agricultural UniversityBeijing 100193China National Academy of Agriculture Green Development China Agricultural UniversityBeijing 100193China College of Resources and Environment/International Magnesium Institute Fujian Agriculture and Forestry UniversityFuzhou 350002China

Large-scale farming by agricultural land transfers has been increasingly promoted in recent years,but the possible impacts on crop production,especially cash crops,and soil acidification remain *** study obtained data for 110 banana plantations in Long’an County,China,and categorized them into small(6.7 ha)to determine banana cultivation,nutrient management,and soil acidification rates on farms of the three *** yield per unit area significantly increased with increased farm size,and large farms had the highest average yield(48.9 t·ha^(−1))with the least *** a significant increase in organic fertilizer and base cation inputs,nitrogen(N)surplus did not differ significantly with increasing farm *** large farms,actual soil acidification rate was significantly lower by 19.1 to 24.0 keq·ha^(−1)·yr^(−1);however,potential soil acidification rate increased with increased overuse of ***,larger banana plantations used fewer mineral N fertilizers reducing the rate of soil acidification and increasing the H+buffering provided by organic *** is concluded that larger farms deliver the dual benefits of higher,less variable banana yield and mitigation of soil acidification by substituting organic N for mineral N fertilizers,supporting sustainable soil management and food production.

关键词： plantations land transfer large-scale farming nutrient management soil acidification

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Overexpression of IbSINA5 Increases Cold Tolerance through a CBF SINA-COR Mediated Module in Sweet Potato

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Phyton-International Journal of Experimental Botany 2021年第3期90卷 761-772页

作者： shiyang li Xue-Ao liu lizi Zhao Huiqing Huang Bei li Zhizhong Song Meixia liang Hongxia Zhang limin Wang Shenglin Zhou Shandong Technology and Business University Yantai264005China The Engineering Research Institute of Agriculture and Forestry Ludong UniversityYantai264025China School of life Sciences Ludong UniversityYantai264025China

Seven in absentia(SINA)family proteins play a central role in plant growth,development and resistance to abiotic ***,their biological function in plant response to cold stress is still largely *** this work,a seven in absentia gene IbSINA5 was isolated from sweet *** real-time polymerase chain reaction(qRT-PCR)analyses demonstrated that IbSINA5 was ubiquitously expressed in various tissues and organs of sweet potato,with a predominant expression in fibrous roots,and was remarkably induced by cold,drought and salt *** localization assays revealed that IbSINA5-GFP fusion protein was mainly localized in cytoplasm and *** of IbSINA5 in sweet potato led to dramatically improved resistance to cold stress in transgenic plants,which was associated with the up-regulated expression of IbCOR(cold-regulated)genes,increased proline production,and decreased malondialdehyde(MDA)and H2O2 accumulation in the leaves of transgenic ***,transient expression of IbCBF3,a C-repeat binding factor(CBF)gene,in the leaf protoplasts of wild type sweet potato plants up-regulated the expression of both IbSINA5 and IbCOR *** results suggest that IbSINA5 could function as a positive regulator in the cold signaling pathway through a CBF-SINA-COR mediated module in sweet potato,and have a great potential to be used as a candidate gene for the future breeding of new plant species with improved cold resistance.

关键词： Cold stress IbSINA5 seven in absentia sweet potato transgenic plant

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Identification of COL3A1 variants associated with sporadic thoracic aortic dissection: a case-control study

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Frontiers of Medicine 2021年第3期15卷 438-447页

作者： Yanghui Chen Yang Sun Zongzhe li Chenze li Lei Xiao Jiaqi Dai shiyang li Hao liu Dong Hu Dongyang Wu Senlin Hu Bo Yu Peng Chen Ping Xu Wei Kong Dao Wen Wang Division of Cardiology Department of Internal MedicineTongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China Hubei Key Laboratory of Genetics and Molecular Mechanism of Cardiologic Disorders Huazhong University of Science and TechnologyWuhan 430030China The First Affiliated Hospital of the Medical College Shihezi UniversityShihezi 832008China State Key Laboratory of Proteomics Beijing Proteome Research CenterNational Center for Protein Sciences(Beijing)Beijing Institute of LifeomicsBeijing 102206China Department of Physiology and Pathophysiology School of Basic Medical SciencesPeking UniversityBeijing 100191China

Thoracic aortic dissection(TAD)without familial clustering or syndromic features is known as sporadic TAD(STAD).So far,the genetic basis of STAD remains *** exome sequencing was performed in 223 STAD patients and 414 healthy controls from the Chinese Han population(N=637).After population structure and genetic relationship and ancestry analyses,we used the optimal sequence kernel association test to identify the candidate genes or variants of *** found that COL3A1 was significantly relevant to STAD(P=7.35×10^(−6))after 10000 times permutation test(P=2.49×10^(−3)).Moreover,another independent cohort,including 423 cases and 734 non-STAD subjects(N=1157),replicated our results(P=0.021).Further bioinformatics analysis showed that COL3A1 was highly expressed in dissected aortic tissues,and its expression was related to the extracellular matrix(ECM)*** study identified a profile of known heritable TAD genes in the Chinese STAD population and found that COL3A1 could increase the risk of STAD through the ECM *** wanted to expand the knowledge of the genetic basis and pathology of STAD,which may further help in providing better genetic counseling to the patients.

关键词： sporadic thoracic aortic dissection exome sequencing gene COL3A1 case–control study extracellular matrix

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Multiple pollutants from crop and livestock production in the Yangtze River: status and challenges

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Frontiers of Agricultural Science and Engineering 2024年第1期11卷 134-139,I0005页

作者： lihua MA shiyang li linfa FANG Xuanjing CHEN Ran XIAO Xiaoxuan SU Zhaolei li Zhaohai BAI lin MA Prakash LAKSHMANAN Xinping CHEN Interdisciplinary Research Center for Agriculture Green Development in Yangtze River Basin College of Resources and EnvironmentSouthwest UniversityChongqing 400715China Water Systems and Global Change Group Wageningen University&Research6708 PB Wageningenthe Netherlands Key Laboratory of Agricultural Water Resources Center for Agricultural Resources ResearchInstitute of Genetic and Developmental BiologyChinese Academy of SciencesShijiazhuang 050021China Key Laboratory of Sugarcane Biotechnology and Genetic Improvement(Guangxi) Ministry of Agriculture and Rural AffairsGuangxi Key Laboratory of Sugarcane Genetic ImprovementSugarcane Research InstituteGuangxi Academy of Agricultural SciencesNanning 530007China Queensland Alliance for Agriculture and Food Innovation University of QueenslandSt Lucia 4067Australia

The rapid increase in the proportion of cash crops and livestock production in the Yangtze River Basin has led to commensurate increases in fertilizer and pesticide inputs. Excessive application of chemical fertilizer, organophosphorus pesticides and inappropriate disposal of agricultural waste induced water pollution and potentially threaten Agriculture Green Development(AGD). To ensure food security and the food supply capacity of the Yangtze River Basin, it is important to balance green and development, while ensuring the quality of water bodies. Multiple pollutants affect the transfer, adsorption, photolysis and degradation of each other throughout the soil-plant-water system. This paper considers the impact of multi-pollutants on the nitrogen and phosphorus cycles especially for crops, which are related to achieving food security and AGD. It presents prospective on theory, modeling and multi-pollutant control in the Yangtze River Basin for AGD that are of potential value for other developing regions.

关键词： Agriculture Green Development crop production livestock production multi-pollutant models multiple pollutants Yangtze River Basin

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CFD-Aided Investigation of Combined Flow Conditioners for Gas Ultrasonic Flow Meter

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Journal of Shanghai Jiaotong university(Science) 2023年第5期28卷 611-620页

作者：袁亚琦李世阳郑佳李明睿 Department of Instrument Science and Engineering Shanghai Jiao Tong UniversityShanghai 200240China 726th Research Institute of China Shipbuilding Industry Corporation Shanghai 201108China

Stable and fully developed gas flow field is crucial for realizing accurate measurement of gas ultrasonicflow meter. To reduce the flow field distortion, a flow conditioner is usually used. However, the traditionalmonotype flow conditioner can only improve the flow field distribution partly. The measurement accuracy of thetransit time ultrasonic flow meter is still affected because of its serious flow field distortion in the complex pipelineconditions. In this paper, to further improve the flow field distribution, a combined conditioner is *** combined flow conditioner is composed of fan-shaped section, turbulent mixing cavity, and honeycomb-shapedsection. The effects of fan blade angle and cavity length on the flow field of the DN50 flow meter are studied usingcomputational fluid dynamics (CFD) simulation. Simulation results indicate that compared with the monotypeconditioner, the combined conditioner has better performance on effectively reducing the swirl and turbulence andproviding more stable and repetitive velocity profiles. Experiments also validate the effectiveness of the combinedconditioner. The flow meter with the combined conditioner has better repeatability of less than 0.2%, which isbetter than those of the monotype conditioners under the same conditions. This work is very useful for accuratemeasurement of gas ultrasonic flow meter, especially for the complex pipeline conditions.

关键词： computational fluid dynamics(CFD) flow conditioners gas ultrasonic flow meter swirl turbulence

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论贿赂犯罪的差序法益构造

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政治与法律 2022年第8期 62-79页

作者：李世阳浙江大学光华法学院浙江杭州310008

贿赂犯罪教义学体系的建构需要统一的保护法益作为指导。在贿赂犯罪的构造上,应超越传统的受贿人与行贿人的两极构造,从分配行政的立场出发,分别从平行的社会一般人、全体国民、国家的视角逐层考察受贿人与行贿人形成的交易关系所侵害... 详细信息

贿赂犯罪教义学体系的建构需要统一的保护法益作为指导。在贿赂犯罪的构造上,应超越传统的受贿人与行贿人的两极构造,从分配行政的立场出发,分别从平行的社会一般人、全体国民、国家的视角逐层考察受贿人与行贿人形成的交易关系所侵害的内容。与贿赂犯罪的这种差序构造相对应,贿赂犯罪的保护法益也由渐进式的三重内容构成,第一重是从与行贿人处于同等的资源竞争地位的平行社会一般人的视角出发,贿赂犯罪侵犯了其获取维系生存和自由发展的公共资源的机会公平性;第二重是从全体国民的视角出发,贿赂犯罪破坏了国民对于凭借自己实力获取相应公共资源的信赖利益;第三重是从国家的视角出发,贿赂犯罪累积性地侵犯国家这一抽象人格体的存在根基。

关键词：差序格局分配行政机会公平性信赖利益国家

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