检索结果-南通市图书馆

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

中药知母组培快繁体系的建立

种子 2024年第3期43卷 143-149页

作者：刘秀秀任俊男狄根森吴立柱马春英河北农业大学农学院河北保定071033 河北农业大学生命科学学院河北保定071033

为了建立知母高效组织培养及快速繁殖体系,将知母的叶片、根茎和幼嫩花葶分别接种于9种组合培养基上,筛选最佳的外植体材料;以MS培养基为基本培养基,通过不同种类激素和浓度的配比试验,筛选出知母离体组培快繁不同阶段的培养基组合;测... 详细信息

为了建立知母高效组织培养及快速繁殖体系,将知母的叶片、根茎和幼嫩花葶分别接种于9种组合培养基上,筛选最佳的外植体材料;以MS培养基为基本培养基,通过不同种类激素和浓度的配比试验,筛选出知母离体组培快繁不同阶段的培养基组合;测定不同种类激素和浓度组合培养基下炼苗移栽成功的知母组培苗芒果苷含量。结果表明,幼嫩花葶为诱导愈伤组织最佳外植体,诱导知母幼嫩花葶产生愈伤组织的培养基组合为MS+1.0 mg/L KT+0.5 mg/L NAA,出愈率为79.40%;诱导愈伤组织产生不定芽的培养基组合为MS+0.5 mg/L 6-BA+0.5 mg/L NAA,生芽率为100%;诱导不定芽生根培养的培养基组合为MS+0.5 mg/L NAA,生根率为100%,且在此培养基组合下炼苗移栽的知母组培苗芒果苷含量最高。

关键词：知母幼嫩花葶组织培养快速繁殖

Fischer-Tropsch wax catalytic cracking for the production of low olefin and high octane number gasoline: Process optimization and heat effect calculation

在线全文

学校读者我要写书评

暂无评论

Petroleum Science 2023年第2期20卷 1255-1265页

作者： Mei Yang Gang Wang Jian-Nian Han Cheng-di Gao Jin-Sen Gao State Key laboratory of Heavy Oil Processing College of Chemical Engineering and and EnvironmentChina University of PetroleumBeijing 102249China College of Science China University of PetroleumBeijing 102249China

To produce low olefin gasoline with high octane number by Fischer-Tropsch (F-T) wax fluid catalytic cracking (FCC) process, operating conditions optimization were carried out in the pilot-scale riser and turbulent fluidized bed (TFB) FCC unit. The experimental results in the riser indicated that under the condition of low reaction temperature and regenerated catalyst temperature, large catalyst-to-oil weight ratio (C/O) and long reaction time, the gasoline olefin content could be reduced to 20.28 wt%, but there is large octane number loss owing to a great loss in high octane number olefin. Therefore, a novel FCC process using the TFB reactor was proposed to strengthen the aromatization reaction. The reaction performance of TFB reactor were investigated. The result demonstrated that the TFB reactor has more significant effect in reducing olefins and improving aromatics. At the expense of certain gasoline yield, the gasoline olefin content reduced to 23.70 wt%, aromatics content could increase to 26.79 wt% and the RON was up to 91.0. The comparison of reactor structure and fluidization demonstrated that the TFB reactor has higher catalyst bed density. The reaction heat and coke combustion heat was calculated indicating the feasibility of its industrial application of the TFB process.

关键词： Fischer-Tropsch wax catalytic cracking Riser TFB Gasoline olefin Reaction heat

Research and development of 780 MPa cold rolling TRIP-aided steel

在线全文

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and Materials 2009年第4期16卷 399-406页

作者： Qiang Liu di Tang Hai-tao Jiang Ren-dong Liu Xiao-yong Tang National Engineering Research Center for Advanced Rolling Technology University of Science and Technology Beijing Beijing 100083 China Researchand Development Center Anshan Iron and Steel （Group） Corp. Anshan 114001 Liaoning China

As an industry-university cooperative project, an experimental research was conducted to develop a new cold-rolled transformation-induced plasticity （TRIP） steel with a tensile strength of 780 MPa and an elongation of 25% under the conditions that some processing parameters were preestablished according to the actual conditions of factory production lines. The optimal heat treatment conditions for obtaining excellent strength-ductility balance, specifically in intercritical annealing temperature and isothermal treatment temperature, were investigated by means of thermal simulation tests. Ultimately the desirable mechanical properties were attained successfully, and the microstructure and retained austenite stability were studied by optical microscopy （OM） and electron back-scattered diffraction （EBSD）. It has been discovered that the sizes of retained austenite grains are generally proportional to the sizes of carbon-clear space （ferrite and bainite） around them, and there is marked selectivity in their transition sequences under stress-strain.

关键词： TRIP steel heat treatment retained austenite stability

Characteristics of alcoholic liver disease and predictive factors for mortality of patients with alcoholic cirrhosis

在线全文

学校读者我要写书评

暂无评论

Hepatobiliary & Pancreatic diseases International 2013年第6期12卷 594-601页

作者： Yan-di Xie Bo Feng Yan Gao lai Wei Peking University People's Hospital Peking University Hepatology Institute Beijing Key Laboratory of Hepatitis C and Immuno-therapy for Liver Disease

BACKGROUND:Alcoholic liver disease is one of the major chronic liver diseases *** aim of the study was to describe the clinical characteristics of alcoholic liver disease and to compare the predictive values of biochemical parameters,complications,Child-Turcotte-Pugh score,model for end-stage liver disease(MELD)score and discriminant function score for the mortality of in-hospital or 3-month after discharge of patients with alcoholic cirrhosis(AC).METHODS:A retrospective record review and statistical analysis were performed on 205 consecutive patients with the discharge diagnosis of alcoholic liver *** models were used to predict the mortality of patients with *** number of variceal hemorrhage,infection,hepatic encephalopathy and hepatocellular carcinoma was analyzed as"numbers of complications".Model 1 consisted of creatinine,white blood cell count,international normalized ratio and"numbers of complications".Model 2 consisted of MELD *** 3included"numbers of complications"and MELD ***:The risk of developing AC was significant for patients with alcohol consumption of higher than 80 g/d(OR=2.807,Pdicting inhospital mortality of models 1,2 and 3 was 0.950,0.886 and 0.911(all Pdicting the 3-month mortality of models 1,2 and 3 was 0.867,0.878 and0.893(all Plationship between alcohol consumption and the risk of developing *** score has a better predictive value than Child-TurcottePugh or discriminant function score for patients with AC,and model 1 or 3 is better than model 2.

关键词： alcoholic liver disease model for end-stage liver disease mortality prognostic factors risk factors

Pancreatic cancer stem cells:Perspectives on potential therapeutic approaches of pancreatic ductal adenocarcinoma

在线全文

学校读者我要写书评

暂无评论

World Journal of Stem Cells 2018年第11期10卷 172-182页

作者： Claudia di carlo Jessica Brandi Daniela Cecconi Department of Biotechnology Proteomics and Mass Spectrometry Laboratory University of Verona

Pancreatic ductal adenocarcinoma is one of the most aggressive solid tumours of the pancreas, characterised by a fve-year survival rate less than 8%. Recent reports that pancreatic cancer stem cells （PCSCs） contribute to the tumorigenesis, progression, and chemoresistance of pancreatic cancer have prompted the investigation of new therapeutic approaches able to directly target PCSCs. In the present paper the non-cancer related drugs that have been proposed to target CSCs that could potentially combat pancreatic cancer are revi-ewed and evaluated. The role of some pathways and deregulated proteins in PCSCs as new therapeutic tar-gets are also discussed with a focus on selected speci-fic inhibitors. Finally, advances in the development of nanoparticles for targeting PCSCs and site-specifc drug delivery are highlighted, and their limitations considered.

关键词： Pancreatic cancer stem cells Pancreatic cancer Therapeutic approaches Pancreas Treatment

Links between COVID-19 and Parkinson’s disease/Alzheimer’s disease:reciprocal impacts,medical care strategies and underlying mechanisms

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Translational Neurodegeneration 2023年第1期12卷 824-848页

作者： Pei Huang Lin-Yuan Zhang Yu-Yan Tan Sheng-di Chen Department of Neurology and Institute of Neurology Ruijin HospitalShanghai Jiao Tong University School of MedicineShanghai 200025China Department of Neurology Shanghai General HospitalShanghai 200080China lab for Translational Research of Neurodegenerative diseases Shanghai Institute for Advanced Immunochemical Studies(SIAIS)Shanghai Tech UniversityShanghai 201210China

The impact of coronavirus disease 2019(COVID-19)pandemic on patients with neurodegenerative diseases and the specific neurological manifestations of COVID-19 have aroused great ***,there are still many issues of concern to be ***,we review the current literature on the complex relationship between COVID-19 and neurodegenerative diseases with an emphasis on Parkinson’s disease(PD)and Alzheimer’s disease(AD).We summarize the impact of COVID-19 infection on symptom severity,disease progression,and mortality rate of PD and AD,and discuss whether COVID-19 infection could trigger PD and *** addition,the susceptibility to and the prognosis of COVID-19 in PD patients and AD patients are also *** order to achieve better management of PD and AD patients,modifications of care strategies,specific drug therapies,and vaccines during the pandemic are also *** last,mechanisms underlying the link of COVID-19 with PD and AD are reviewed.

关键词： COVID-19 SARS-CoV-2 Parkinson’s disease Alzheimer’s disease Mechanism

Shear Model of Metal Melt Flowing on Vibration Wall and Effect of Shear Stress on Solidification Microstructure

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Acta Metallurgica Sinica(English Letters) 2018年第6期31卷 650-658页

作者： Ren-Guo Guan Xiang Wang Ying-Qiu Shang di Tie Run-Ze Chao School of Materials Science and Engineering Northwestern Polytechnical University Xi'an 710072 China School of Materials Science and Engineering Northeastern University Shenyang 110819 China Luoyang Ship Material Research Institute Luoyang 471000China

In this work,the shear model of metal melt flowing on vibration surface is established,and coupling effects of vibration and shear on the distribution of shear stress in melt and melt solidification microstructure are *** results show that the transition of melt from laminar flow to turbulent flow occurs earlier with increasing vibration frequency and vibration *** the laminar flow melt,shear stress in melt decreases with increasing vertical length,but it decreases firstly and then stabilizes with increasing flow *** the turbulent flow melt,shear stress decreases firstly and then stabilizes with increasing vertical length,but it increases with increasing flow *** the increase in vibration frequency and amplitude,shear stress along flow direction in laminar flow melt increases,while shear stresses along both flow direction and vertical direction in turbulent flow melt *** stress in melt decreases with increasing length along vertical *** the increase in flow length,shear stress decreases firstly and then stabilizes in laminar flow melt,while it increases in turbulent flow *** the increase in vibration frequency and amplitude,shear stress increases in laminar flow melt,while it stabilizes in turbulent flow *** on theoretical calculation,the maximum shear stress in melt during vibration shear flow is always much lower than the yield strength of a-Al grain,so the shear stress induced by vibration shear flow cannot break columnar crystal,which agrees with the experiment ***,the model can explain the shear constitutive relation of melt flow on vibration surface relatively well.

关键词： Solidification Flow near surface Shear Vibration Columnar crystal

High efficient multipacket decoding approach for network coding in wireless networks

在线全文

学校读者我要写书评

暂无评论

The Journal of China Universities of Posts and Telecommunications 2013年第1期20卷 95-100页

作者： YAO Yu-kun WEN Ya-di REN Zhi LIU Zhi-hu Chongqing Key laboratory of Mobile Communication Technology Chongqing University of Posts and Telecommunications

To improve the performance of transmission by reducing the number of transmission and network overhead of wireless single-hop networks, this paper presents a high efficient multipacket decoding approach for network coding （EMDNC） in wireless networks according to the idea of encoding packets which cannot be decoded and are stored in buffer by receiving nodes, the lost packets can be recovered from these encoded packets. Compared with the network coding wireless broadcasting retransmission （NCWBR）, EMDNC can improve the efficiency of decoding and reduce the number of retransmission and transmission delay. Simulation results reveal that EMDNC can effectively reduce the number of retransmission and network overhead.

关键词： wireless single-hop networks network coding number ofretransmission transmission delay network overhead

Mobile-Service Based Max-Min Fairness Resource Scheduling for Heterogeneous Vehicular Networks

在线全文

学校读者我要写书评

暂无评论

China Communications 2015年第S2期12卷 10-18页

作者： ZHANG Yu XIONG Ke AN Fengping di Xiaofei SU Jingtao School of Computer and Communication Engineering University of Science and TechnologyBeijing School of Computer and Information Technology Beijing Jiaotong UniversityBeijing National Mobile Communications Research laboratory Southeast University

This paper investigates the resource scheduling for heterogeneous vehicular networks, where some moving vehicles are selected and scheduled as helping relays to assist information transmission between the roadside infrastructure and other moving vehicles. For such a system, we propose a mobile-service based max-min fairness resource scheduling scheme, where service amount which is more suitable for high mobility scenarios is adopted to characterize the information transmission capacity of the links and the max-min criteria is adopted to meet the fairness requirement of the moving vehicles. Simulation results demonstrate the effectiveness of our proposed scheme. It is shown that our proposed scheme archives higher throughput and better fairness compared with random scheduling scheme and non-relaying scheme.

关键词： heterogeneous vehicular network vehicular communications cooperative relaying max-min fairness