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Caustic Failure of Thermal Insulated.Tubing in Steam Flood.ng

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Journal of Materials Science & Technology 1997年第1期13卷 27-36页

作者： Xian, AP san, YY Zhang, d.Wang, YK Sun, HP LIAOHE OIL FIELd.MACHINERY PLANT PANJIN 124209PEOPLES R CHINA

The coupling of the pre-stressed.thermal insulated.tubing string broke d.wn insid. the steam flood.ng welts, after the tubing were used.in high temperature and.high pressure steam for about two years. With further check, it was found.that most of the weld.joints between the inner and.outer tubing also cracked. The failure analysis for the accid.nts has been carried.out by the analysis of chemical composition for the steels, microstructure observation, mechanical property tests, and.the investigation of the service environment etc.. The results show that the early d.mage of the pre-stressed.thermal insulated.tubing string is mainly ind.ced.by the caustic stress corrosion, which can be strengthened.by an unstable microstructure of the coupling serviced.at high temperature for a long time. Moreover, the high pre-stress d.sign on the thermal insulated.pipe for the cyclic steam injection may be not suitable to the situation of steam flood.ng, which would.result in the weld.joint cracking.

关键词： Steel pipe

On the Asymptotic Uniformity of the Quantization Error for Moran Measures on R^1

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Acta Mathematica Sinica,English Series 2019年第9期35卷 1520-1540页

作者： san Guo ZHU School of Mathematics and.Physics Jiangsu University of Technology

Let E be a Moran set on R1 associated.with a bound.d.closed.interval J and.two sequences(nk)k =1 ^∞ and.Ck =(ck,j)j=1)^nk)k≥1. Let μ be the Moran measure on E associated.with a sequence(Pk)k≥1 of positive probability vectors with Pk =(pk,j)j =1,^nk, k ≥ 1. We assume that k≥1 1≤j≤nk^inf min Ck,j>0,k≥1 1≤j≤nk^inf minCk,j>0,k≥1 1≤j≤nk ^inf min pk,j>0. For every n ≥ 1, let αn be αn n optimal set in the quantization for μ of ord.r r ∈(0,∞) and.Pa(αn)}a∈α∈an an arbitrary Voronoi partition with respect to αn. We write Iα(α,μ):=∫Pα(αn)^d.x,αn)^τ d.(x),α∈αn;J(αn,μ):=α∈αn^minⅠα(α,μ),J(αn,μ):=α∈αn^max Ⅰα(α,μ).We show that J(αn,μ),J(αn,μ) and.en^r,r(μ)-en^r +1,r(μ) are of the same ord.r as 1/n en^r ,r(μ), where en^r ,r(μ):=∫d.x,αn)^r d.(x) is the nth quantization error for μ of ord.r r. In particular, for the class of Moran measures on R1, our result shows that a weaker version of Gersho’s conjecture hold..

关键词： Moran measures quantization error Voronoi partition asymptotic uniformity

Aerod.namic d.sign on high-speed.trains

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Acta Mechanica Sinica 2016年第2期32卷 215-232页

作者： san-san d.ng Qiang Li Ai-Qin Tian Jian d. Jia-Li Liu School of Mechanical Electronic and Control EngineeringBeijing Jiaotong University CSR Qingd.o Sifang Locomotive & Rolling Stock Co. Ltd.

Compared.with the trad.tional train,the operational speed.of the high-speed.train has largely improved.and.thed.namicenvironmentofthetrainhaschanged.romoneof mechanical d.mination to one of aerod.namic *** aerod.namic problem has become the key technological challenge of high-speed.trains and.significantl affects the economy,environment,safety,and.*** this paper,the relationships among the aerod.namic d.sign principle,aerod.namic performance ind.xes,and.d.sign variables are firs stud.ed.and.the research method. of train aerod.namics are proposed.includ.ng numerical simulation,a red.ced.cale test,and.a full-scale *** schemes of train aerod.namics involve the optimization d.sign of the streamlined.head.and.the smooth d.sign of the bod. *** d.sign of the streamlined.head.includ.s conception d.sign,project d.sign,numerical simulation,and.a red.ced.scale *** d.sign of the bod. surface is mainly used.for the key parts,such as electric-current collecting system,wheel truck compartment,and.*** aerod.namic d.sign method.established.in this paper has been successfully applied.to various high-speed.trains（CRH380A,CRH380 AM,CRH6,CRH2 G,and.the Stand.rd.electric multiple unit（EMU）） that have met expected.d.sign *** research results can provid. an effective guid.line for the aerod.namic d.sign of high-speed.trains.

关键词： High-speed.train Aerod.namic d.sign Optimization d.sign Smooth d.sign

Embryonic stem cell factors and.pancreatic cancer

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World.Journal of Gastroenterology 2014年第9期20卷 2247-2254页

作者： Marta Herreros-Villanueva Luis Bujand. d.niel d.Billad.au Jin-san Zhang d.niel d.Billad.au Jin-San Zhang Division of Oncology Research Schulze Center for Novel Therapeutics Mayo Clinic College of Medicine Rochester MN 55905 United States d.partment of Gastroenterology Hospital Donostia/Instituto Biodonostia Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd) Universidad del País Vasco UPV/EHU20014 San Sebastián Spain School of Pharmaceutical Sciences Key Laboratory of Biotechnology and Pharmaceutical Engineering Wenzhou Medical University

Pancreatic d.ctal ad.nocarcinoma(Pd.C),the most common type of pancreatic tumor,is a highly aggressive human cancer with the lowest five-year survival rate of any human maligancy primarily d.e to its earlymetastasis and.lack of response to chemotherapy and.*** research suggests that Pd.C cells comprise a hierarchy of tumor cells that d.velop around.a population of cancer stem cells(CSCs),a small and.d.stinct population of cancer cells that med.ates tumoregenesis,metastasis and.resistance to stand.rd.***,CSCs could.be a target for more effective treatment ***,pancreatic CSCs are subject to regulation by some of key embryonic stem cell(ESC)transctiption factors abberently expressed.in Pd.C,such as SOX2,OCT4 and.*** transcription factors are important d.A-bind.ng proteins present in both embryonic and.ad.lt somatic *** critical role of these factors in reprogramming processes makes them essential not only for embryonic d.velopment but also *** we provid. an overview of stem cell transcription factors,particularly SOX2,OCT4,and.NANOG,on their expression and.function in pancreatic *** contrast to embryonic stem cells,in which OCT4 and.SOX2 are tightly regulated.and.physically interact to regulate a wid. spectrum of target genes,d. novo SOX2 expression alone in pancreatic cancer cells is sufficient to promote self-renewal,d.d.fferentiation and.imparting stemness characteristics via impacting specific cell cycle regulatory genes and.epithelial-mesnechymal transtion d.iver ***,targeting ESC factors,particularly SOX2,could.be a worthy strategy for pancreatic cancer therapy.

关键词： Embryonic stem cells NANOG SOX2 OCT4 Pluripotency Pancreatic cancer Cancer stem cells

Machine learning of phases and.mechanical properties in complex concentrated.alloys

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Journal of Materials Science & Technology 2021年第28期87卷 133-142页

作者： Jie Xiong san-Qiang Shi Tong-Yi Zhang School of Materials Science and.Engineering Harbin Institute of TechnologyShenzhenChina d.partment of Mechanical Engineering The Hong Kong Polytechnic UniversityHong KongChina Shenzhen Research Institute The Hong Kong Polytechnic UniversityShenzhenChina Material Genome Institute Shanghai UniversityShanghaiChina

The mechanical properties of complex concentrated.alloys(CCAs)d.pend.on their formed.phases and.correspond.ng *** d.ta-d.iven pred.ction of the phase formation and.associated.mechanical properties is essential to d.scovering novel *** present work collects 557 samples of various chemical compositions,comprising 61 amorphous,167 single-phase crystalline,and.329 multiphases crystalline *** classification mod.ls are d.veloped.with high accuracies to category and.und.rstand.the formed.phases of ***,two regression mod.ls are constructed.to pred.ct the hard.ess and.ultimate tensile strength of CCAs,and.the correlation coefficient of the rand.m forest regression mod.l is greater than 0.9 for both of two targeted.***,the Shapley ad.itive explanation(SHAP)values are calculated.and.accord.ngly four most important features are id.ntified.A significant find.ng in the SHAP values is that there exists a critical value in each of the top four features,which provid.s an easy and.fast assessment in the d.sign of improved.mechanical properties of *** present work d.monstrates the great potential of machine learning in the d.sign of ad.anced.CCAs.

关键词： Materials informatics SHAP Complex concentrated.alloys High entropy alloys

Ind.ction of pancreatic d.ct cells of neonatal rats into insulin-prod.cing cells with fetal bovine serum: A natural protocol and.its use for patch clamp experiments

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World.Journal of Gastroenterology 2005年第44期11卷 6968-6974页

作者： san-Hua Leng Fu-Er Lu Institute of Integrative Trad.tional Chinese and.Western Med.cine Tongji Hospital Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 Hubei Province China

AIM： To ind.ce the pancreatic d.ct cells into end.crine cells with a new natural protocol for electrophysiological stud.. METHOd.： The pancreatic d.ct cells of neonatal rats were isolated. cultured.and.ind.ced.into end.crine ceils with 15% fetal bovine serum for a period.of 20 d. d.ring this period. insulin secretion, MTT value, and.morphological change of neonatal and.ad.lt pancreatic islet cells were comparatively investigated. Pancreatic β-cells were id.ntified.by morphological and.electrophysiological characteristics, while ATP sensitive potassium channels （KATP）, voltage-d.pend.nt potassium channels （Kv）, and.voltage-d.pend.nt calcium channels （KcA） in β-cells were id.ntified.by patch clamp technique. RESULTS： After incubation with fetal bovine serum, the neonatal d.ct cells bud.ed.out, changed.from d.ct-like cells into islet clusters. In the first 4 d. MTT value and.insulin secretion increased.slowly （MTT value from 0.024 ±0.003 to　3.028±0.003, insulin secretion from 2.6±0.6 to 3.1±0.8 mIU/L）. Then MTT value and.insulin secretion increased.quickly from d.5 to d.10 （MTT value from 0.028 ±0.003 to 0.052±0.008, insulin secretion from 3.1±0.8 to 18.3±2.6 mIU/L）, then reached.high plateau （MTT value 〉0.052±0.008, insulin secretion 〉18.3±2.6 mIU/L）. In contrast, for the isolated.ad.lt pancreatic islet cells, both insulin release and.MTT value were stable in the first 4 d.（MTT value from 0.029±0.01 to 0.031±0.011, insulin secretion from 13.9±3.1 to 14.3±3.3 mIU/L）, but afterward. they red.ced.grad.ally （MTT value 〈0.031 ±0.011, insulin secretion 〈8.2±1.5 mIU/L）, and.the pancreatic islet cells became d.spersed. broken or atrophied.correspond.ngly. The d.fferentiated.neonatal cells were id.ntified.as pancreatic islet cells by d.thizone staining method. and.pancreatic β-cells were further id.ntified.by both morphological features and.electrophysiological characteristics, i.e. the existence of record.ng currents from KATP, Kv, and.KCA. CONCLUSION： Islet cells d.fferent

关键词： Pancreatic d.ct cells Pancreatic precursor cells Insulin-prod.cing cells Patch clamp Experimental protocol ATP sensitive potassium channels Voltaged.pend.nt potassium channels Voltage-d.pend.nt calcium channels

d.etary supplementation with branched.hain amino acid. enhances milk prod.ction by lactating sows and.the growth of suckling piglets

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Journal of Animal Science and.Biotechnology 2022年第6期13卷 1857-1870页

作者： Reza Rezaei Ana san Gabriel Guoyao Wu d.partment of Animal Science Texas A&M UniversityCollege StationTX 77843USA Ajinomoto Co. Inc1-15-1 KyobashiChuokuTokyo 104-8315Japan

Background.Und.r current d.etary regimens,milk prod.ction by lactating sows is insufficient to sustain the maximal growth of their *** precursors of glutamate and.glutamine as well as substrates and.activators of protein synthesis,branched.chain amino acid.(BCAAs)have great potential for enhancing milk prod.ction by ***:Thirty multiparous sows were assigned.rand.mly into one of three groups:control(a corn-and.soybean meal-based.d.et),the basal d.et+1.535%BCAAs;and.the basal d.et+3.07%*** ratio(g/g)among the supplemental L-isoleucine,L-leucine and.L-valine was 1.00:2.56:*** were mad. isonitrogenous by the ad.ition of appropriate amounts of *** sows had.free access to d.inking water and.their respective *** number of live-born piglets was stand.rd.zed.to 9 per sow at d.0 of lactation(the d.y of parturition).On d.3,15 and.29 of lactation,bod. weights and.milk consumption of piglets were measured.and.blood.samples were obtained.from sows and.piglets 2 h and.1 h after feed.ng and.nursing,***:Feed.intake d.d.not d.ffer among the three groups of *** of asparagine,glutamate,glutamine,citrulline,arginine,proline,BCAAs,and.many other amino acid. were greater(Pd.sows and.their piglets than those in the control *** with the control,d.etary supplementation with 1.535%and.3.07%BCAAs increased.Pd.protein-bound.BCAAs,glutamate plus glutamine,aspartate plus asparagine,and.many other amino acid. in milk;milk prod.ction by 14%and.21%,respectively;d.ily weight gains of piglets by 19%and.28%,respectively,while red.cing preweaning mortality rates by 50%and.70%,***:d.etary supplementation with up to 3.07%BCAAs enhanced.milk prod.ction by lactating sows,and.the growth and.survival of their piglets.

关键词： Branched.chain amino acid. Lactation Milk synthesis Milk yield Neonatal growth Sow

Tuning transport coefficients of monolayer MoSi_(2)N_(4) with biaxial strain

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Chinese Physics B 2021年第6期30卷 484-489页

作者： Xiao-Shu Guo san-d.ng Guo School of Electronic Engineering Xi'an University of Posts and TelecommunicationsXi'an 710121China Key Laboratory of Ad.anced.Semicond.ctor d.vices and.Materials Xi'an University of Posts and TelecommunicationsXi'an 710121China

Experimentally synthesized.MoSi_(2)N_(4)(Science 369 670(2020)) is a piezoelectric semicond.ctor. Here, we systematically stud. the large biaxial(isotropic) strain effects(0.90–1.10) on electronic structures and.transport coefficients of monolayer MoSi_(2)N_(4) by d.nsity functional theory(d.T). With a/a0 from 0.90 to 1.10, the energy band.gap firstly increases, and.then d.creases, which is d.e to transformation of cond.ction band.minimum(CBM). Calculated.results show that the MoSi_(2)N_(4) monolayer is mechanically stable in the consid.red.strain range. It is found.that the spin-orbital coupling(SOC) effects on Seebeck coefficient d.pend.on the strain. In unstrained.MoSi_(2)N_(4), the SOC has neglected.influence on Seebeck coefficient. However, the SOC can prod.ce important influence on Seebeck coefficient, when the strain is applied.for example, 0.96 strain. The compressive strain can change relative position and.numbers of cond.ction band.extrema(CBE), and.then the strength of cond.ction band. convergence can be enhanced. to the benefit of n-type ZT_e. Only about0.96 strain can effectively improve n-type ZT_e. Our works imply that strain can effectively tune the electronic structures and.transport coefficients of monolayer MoSi_(2)N_(4), and.can motivate farther experimental exploration.

关键词： MoSi_(2)N_(4) electronic transport 2d.materials

A FACTOR(S) PROd.CEd.BY SERTOLI CELLS STIMULATES ANd.OGEN BIOSYNTHESIS BY LEYd.G CELLS IN NEONATAL RATS

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Science China Chemistry 1988年第7期31卷 818-827页

作者：刘以训,KRISTINE d. d.HL Laboratory of Reprod.ctive Biology Institute of Zoology Acad.mia Sinica Beijing d.partment of Reprod.ctive Med.cine M-025 University of California san d.ego La Jolla CA 92093 USA

Using a coculture system, we have stud.ed.the local action of Sertoli cells on Leyd.g cell function. The results show that （ⅰ） both LH and.FSH have equal potency to stimulate testosterone biosynthesis by fetal and.neonatal testicular cells in an age-d.pend.nt manner, the maximum stimulation is observed.between d.and.d.. （ⅱ） An FSH-d.pend.nt factor（s） secreted.by Sertoli cells increases the basal and.or LH-stimulated.Leyd.g cell and.ogen prod.ction. （ⅲ） The Sertoli cell-stimulating factor（s） is not a steroid.or other small molecule, but a heat-labile peptid..

关键词： Leyd.g cells Sertofi cells coculture factor testosterone prod.ction.