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Particuology 2015年第5期13卷 95-99页

作者： Haifeng Jiang Qianghui Xu Chao Huang lin shi Key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Thermal Engineering Tsinghua University

Nanofluids were prepared by dispersing Cu nanoparticles （-20nm） in n-tetradecane by a two-step method. The effective thermal conductivity was measured for various nanoparticle volume fractions （0.0001-0.02） and temperatures （306.22-452.66 K）. The experimental data compares well with the Jang and Choi model, The thermal conductivity enhancement was lower above 391.06 K than for that between 306,22 and 360,77 K, The interfacial thermal resistance increased with increasing temperature, The effective thermal conductivity enhancement was greater than that obtained with a more viscous fluid as the base media at 452,66 K because of nanoconvection induced by nanoparticle Brownian motion at high temoerature.

关键词： Nanofluid Thermal conductivity High temperature Brownian motion

Review of solution growth techniques for 4H-SiC single crystal

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China Foundry 2023年第2期20卷 159-178页

作者： Gang-qiang Liang Hao Qian Yi-lin Su lin shi Qiang Li Yuan Liu School of Materials Science and Engineering Tsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology(Ministry of Education) Beijing 100084China

Silicon carbide(SiC),a group IV compound and wide-bandgap semiconductor for high-power,high-frequency and high-temperature devices,demonstrates excellent inherent properties for power devices and specialized high-end *** growth is thermodynamically favorable for producing SiC single crystal ingots with ultra-low dislocation density as the crystallization is driven by the supersaturation of carbon dissolved in Si-metal ***,solution growth is conducive to the growth of both N-and P-type SiC,with doping concentrations ranging from 10^(14)to 10^(19)cm^(-3).To date,4-inch 4H-SiC substrates with a thickness of 15 mm produced by solution growth have been unveiled,while substrates of 6 inches and above are still under *** on top-seeded solution growth(TSSG),several growth techniques have been developed including solution growth on a concave surface(SGCS),melt-back,accelerated crucible rotation technique(ACRT),two-step growth,and facet ***-parameters of the solution growth including meniscus,solvent design,flow control,dislocation conversion,facet growth,and structures of graphite components make high-quality single crystal growth *** this paper,the solution growth techniques and corresponding parameters involved in SiC bulk growth were reviewed.

关键词： wide-bandgap semiconductor silicon carbide bulk growth of single crystal process parameters

Initial pre-stress finding procedure and structural performance research for Levy cable dome based on linear adjustment theory

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2007年第9期8卷 1366-1372页

作者： ZHANG Li-mei CHEN Wu-jun DONG shi-lin Space Structures Research Center Shanghai Jiao Tong University Shanghai 200030 China

The cable-strut structural system is statically and kinematically indeterminate. The initial pre-stress is a key factor for determining the shape and load carrying capacity. A new numerical algorithm is presented herein for the initial pre-stress finding procedure of complete cable-strut assembly. This method is based on the linear adjustment theory and does not take into account the material behavior. By using this method,the initial pre-stress of the multi self-stress modes can be found easily and the cal-culation process is simplified and efficient also. Finally,the initial pre-stress and structural performances of a particular Levy cable dome are analyzed comprehensively. The algorithm has proven to be efficient and correct,and the numerical results are valuable for practical design of Levy cable dome.

关键词： linear adjustment theory Cable-strut structure Initial pre-stress Levy cable dome Structural performances analysis

Hypericin: chemical synthesis and biosynthesis

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Chinese Journal of Natural Medicines 2014年第2期12卷 81-88页

作者： HUANG lin-Fang WANG Zeng-Hui CHEN shi-lin Institute of Medicinal Plant Development Chinese Academy of Medical Sciences & Peking Union Medical College

Hypericin is one of the most important phenanthoperylene quinones extracted mainly from plants of the genus Hypericum belonging to the sections Euhypericum and Campylosporus of Keller's classification. Widespread attention to the antiviral and anti-tumor properties of hypericin has spurred investigations of the chemical synthesis and biosynthesis of this unique compound. However, the synthetic strategies are challenging for organic and biological chemists. In this review, specific significant advances in total synthesis, semi-synthesis, and biosynthesis in the past decades are summarized.

关键词： Hypericin Total synthesis Semi-synthesis Biosynthesis

Herbgenomics facilitates biological study of TCM

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Chinese Journal of Natural Medicines 2020年第8期18卷 561-562页

作者： LI Xi-Wen CHEN shi-lin Institute of Chinese Materia Medica China Academy of Chinese Medical Sciences

Traditional Chinese Medicine (TCM) has been used for more than 5000 years and has attracted more and more worldwide attention because of its significant effect in prevention and treatment of diseases. However, the genetic background,the physio-ecological characteristics, and the molecular mechanisms of most herbs are poorly understood. TheHuman Genome Project opens the biological Era. Genomics

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Activation Effect of Cathartic Natural Compound Rhein to CFTR Chloride Channel

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Chemical Research in Chinese Universities 2006年第3期22卷 312-314页

作者： shi lin-lin XU Li-na HOU Shu-guang lin Sen YANG Hong MA Tong-hui Membrane Channel Research Laboratory Northeast Normal University Changchun 130024 P. R. China Faculty o Life Sciences Liaoning Normal University Dalian 116029 P. R. China China-Japan Union Hospital Jilin University Changchun 130033 P. R. China

The cystic fibrosis transmembrane conductance regulator （CFFR） is a cAMP-activated chloride channel expressed in intestinal exoerine glands, which plays a key role in intestinal fluid secretion. A natural anthraquinone ac tivator of CFTR Cl^- channel, rhein, was identified by screening 217 single compounds from Chinese herbs via a cellbased halide-sensitive fluorescent assay. Rhein activates CFTR Cl^- transportation in a dose-dependent manner in the presence of cAMP with a physiological concentration. This study provides a novel molecular pharmacological mechanism for the laxative drugs in Treditional Chinese Medicine such as aloe, cascara and senna.

关键词： CFTR chloride channel Anthraquinone Laxative drug

Oil production rate predictions for steam assisted gravity drainage based on high-pressure experiments

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Science China(Technological Sciences) 2013年第2期56卷 324-334页

作者： GUO Jia ZAN Cheng MA DeSheng shi lin State Key Laboratory of Enhanced Oil Recovery Research Institute of Petroleum Exploration and DevelopmentPetro China Key Laboratory of Thermal Science and Power Engineering of Ministry of Education Department of Thermal EngineeringTsinghua University State Key Laboratory of Enhanced Oil Recovery Research Institute of Petroleum Exploration and DevelopmentPetroChina

Dual-well steam assisted gravity drainage(SAGD) has significant potential for extra-heavy oil *** is conducting two dual-well SAGD pilot projects in the Fengcheng extra-heavy oil ***,direct predictions of the oil production rate by algebraic models rather than complex numerical models are of great importance for designing and adjusting the SAGD operations.A low-pressure scaled physical simulation was previously used to develop two separate theoretical models corresponding to the two different growth stages observed in the SAGD steam chambers,which are the steam chamber rising stage and the steam chamber spreading stage.A high-pressure scaled model experiment is presented here for one dual-well SAGD pattern to further improve the prediction models to reasonably predict oil production rates for full *** that significantly affect the oil recovery during SAGD were scaled for the model size based on the reservoir characteristics of the Fengcheng reservoir in *** results show the relationship between the evolution of the steam chamber and the oil production rate during the entire production ***-pressure scaled model test was used to improve the gravity drainage models by modifying empirical factors for the rising model and the depletion model.A new division of the SAGD production regime was developed based on the relationship between the oil production rate and the evolution of steam chamber.A method was developed to couple the rising and depletion models to predict oil production rates during the SAGD production,especially during the transition *** method was validated with experiment data and field data from the *** model was then used to predict the oil production rate in the Fengcheng reservoir in China and the Athabasca reservoir in Canada.

关键词： extra-heavy oil steam assisted gravity drainage (SAGD) physical simulation theoretical model

A comprehensive approach for assessing the economic contribution of forage and livestock improvement options to smallholder farming enterprises

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Journal of Integrative Agriculture 2015年第8期14卷 1573-1580页

作者： Neil Mac Leod Scott Waldron WEN shi-lin Agriculture Flagship Commonwealth Scientific and Industrial Research Organisation (CSIRO) University of Queensland Red Soils Experimental Station Chinese Academy of Agricultural Sciences

The importance of livestock production activities to improving the livelihoods of smallholder farming households and the efficiency of their underlying farming systems is increasingly recognized.A rapid increase in livestock numbers, especially beef cattle, and special purpose forages is being promoted for smallholder farms which have traditionally undertaken subsistence cropping activities or simple livestock rearing activities using low quality *** limited plantings of specialized forages combined with a poor knowledge of animal nutrition are a challenge to establishing sustainable livestock enterprises, much public policy and research is now being focused on the use of new forages and improved feeding practices.A number of economic studies have suggested that specialized forage growing and livestock feeding activities can make a positive contribution to smallholder *** studies have typically compared the total level of farm or household income with and without livestock *** attention is given to how much the new forage or livestock activities actually contribute to or draw resources from other farm activities to assess their real economic contribution to the enterprise, and the availability of simple tools to assist in making such assessments are *** paper describes a simple modelling approach that was developed for an Australian Centre for International Agricultural Research（ACIAR）-supported project to explore the real as opposed to apparent economic impact of integrating improved forages and livestock within smallholder farming systems in the Red Soils region of south-central *** of the model is demonstrated using a simple case study of a smallholder enterprise that plans to introduce a new beef cattle rearing activity to its existing farm activity *** case study highlights the importance of explicitly valuing transfers of resources between different farm activities to gauge the real contribution o

关键词： smallholder farming systems economics resource transfers opportunity costs economic profit

Fabrication and analysis of nano-structured thermal spraying feeds

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中国有色金属学会会刊：英文版 2004年第Z1期14卷 83-87页

作者： YE Xiong-lin MA shi-ning LI Chang-qing National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China National Key Laboratory for Remanufacturing Academy of Armored Force Engineering Beijing 100072 China

A kind of thermal spray nanostructured Al2O3 and TiO2 feeds fabricating technology was *** nanogranules prepared by spray drying were heat treated in order to be dense, and there were two sintering technologies used, i.e. high temperature electric furnace sintering and high velocity flame sintering, respectively. The results indicate feeds phase components using high temperature electric furnace sintering at 1 200 ℃,1 300 ℃ and 1 400 ℃ do not change, and grain sizes of nano-Al2O3 and TiO2 grow little at 1 200 ℃ and 1 300 ℃,while grain sizes of nano-Al2O3 and TiO2 grow obviously, and the grain size of nano-TiO2 is larger than 100 nm at 1400 ℃. Phase components of the feeds using high velocity flame sintering change, where α-Al2O3 changes to γ-Al2O3 and rutile TiO2 changes to brookite TiO2, though grain size of nano-Al2O3 does not grow and is less than 100 nm because cooling velocity is too quick. Compared with these two heat treatment technology, the technology using electric furnace to treat nanostructured Al2O3 and TiO2 feeds is more suitable.

关键词： nanostructured feeds thermal spray heat treatment

Nomogram model predicting the overall survival for patients with primary gastric mucosa-associated lymphoid tissue lymphoma

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World Journal of Gastrointestinal Oncology 2023年第3期15卷 533-545页

作者： Dan Wang Xin-lin shi Wei Xu Rui-Hua shi Medical School Southeast UniversityNanjing 210009Jiangsu ProvinceChina Department of Gastroenterology Zhongda HospitalAffiliated Hospital of Southeast UniversityNanjing 210009Jiangsu ProvinceChina Laboratory of Gastroenterology Medical School of Southeast UniversityNanjing 210009Jiangsu ProvinceChina Department of Respiratory and Critical Care Medicine Affiliated Hospital of Yangzhou UniversityYangzhou 225001Jiangsu ProvinceChina

BACKGROUND Increasingly extranodal marginal B-cell lymphoma of mucosa-associated lymphoid tissue,known as mucosa-associated lymphoid tissue(MALT)lymphoma,is a type of non-Hodgkin’s *** prognosis of primary gastric MALT(GML)patients can be affected by many *** risk factors,including age,type of therapy,sex,stage and family hematologic malignancy history,also have significant effects on the development of the *** available data are mainly focused on epidemiology;in contrast,few studies have investigated the prognostic variables for overall survival(OS)in patients with primary *** on the realities above,we searched a large amount of data on patients diagnosed with primary GML in the Surveillance,Epidemiology and End Results(SEER)*** aim was to develop and verify a survival nomogram model that can predict the overall survival prognosis of primary GML by com-bining prognostic and determinant *** To create an effective survival nomogram for patients with primary gastric *** All data of patients with primary GML from 2004 to 2015 were collected from the SEER *** primary endpoint was *** on the LASSO and COX regression,we created and further verified the accuracy and effectiveness of the survival nomogram model by the concordance index(C-index),calibration curve and timedependent receiver operating characteristic(td-ROC)*** A total of 2604 patients diagnosed with primary GML were selected for this study.A total of 1823 and 781 people were randomly distributed into the training and testing sets at a ratio of 7:*** median follow-up of all patients was 71 mo,and the 3-and 5-year OS rates were 87.2%and 79.8%,***,sex,race,Ann Arbor stage and radiation were independent risk factors for OS of primary GML(all P<0.05).The C-index values of the nomogram were 0.751(95%CI:0.729-0.773)and 0.718(95%CI:0.680-0.757)in the training and testing cohorts,respectively,showing the good discrimi

关键词： Primary gastric mucosa-associated lymphoid tissue lymphoma Nomogram Prognosis Overall survival SEER database