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Ac.a g.olog.c. Sinic.(Eng.ish Edition) 2009年第5期83卷 860-867页

作者： c.rlos A.c.NSOLE g.NELLA Mig.el g.IFFIN Florenc.o g.Ac.NOLAZA Instituto Superior de c.rrelac.on g.olog.c.(INSUg.O-c.NIc.T) TucumanArgentina Division Paleozoolog.a de Invertebrados Facultad de Ciencias Naturales y MuseoUniversidad Nacional de la Plata(UNLP-CONICET)Buenos AiresArgentina

We present results tending.to c.arac.erize the new rec.rds of invertebrates from the Yac.raite Formation （Maastric.tian-Danian）. The fossils reported c.me from two stratig.aphic.sec.ions exposed in the surrounding. of Maimara and Jueya, provinc. of Jujuy, northwestern Arg.ntina. The selec.ion was based on g.olog.c.l and paleontolog.c.l evidenc.. The rec.vered fossils inc.ude g.stropods and invertebrate fossil trac.s, inc.uding.Planolites, Skolithos and g.stroc.anoelites ic.nog.nus. As result of our review, we disc.ssed the possibility of assig.ing.the analyzed g.stropods to the family Zyg.pleuridae （g.ne. et. sp. indet.）, as an approximation to the taxonomic.resolution of this fossil fauna. The trac. fossils were assig.ed to the arc.etypic.l g.ossifung.tes ic.nofac.es. The study of the fossil assemblag. allowed us to define a shallow depositional environment, c.arac.eristic.of a marine c.ntext with hig.-energ. c.nditions.

关键词： g.stropod g.ossifung.tes Yac.raite Formation

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不同类型土壤与辣椒风味品质的相关性研究

西南大学学报（自然科学版） 2024年第1期46卷 1-16页

作者：杨梅胡晓婷徐卫红西南大学资源环境学院重庆400715 四川省农业科学院作物研究所成都610066

为探究辣椒的风味品质与不同类型土壤的相关关系,采用相关分析和PLS-DA分析法对不同类型土壤(重庆紫色土、成都水稻土)辣椒的辣椒素、维生素c.游离氨基酸和挥发性成分进行鉴定.结果表明,紫色土辣椒的辣椒素、维生素c.量分数显著低于... 详细信息

为探究辣椒的风味品质与不同类型土壤的相关关系,采用相关分析和PLS-DA分析法对不同类型土壤(重庆紫色土、成都水稻土)辣椒的辣椒素、维生素c.游离氨基酸和挥发性成分进行鉴定.结果表明,紫色土辣椒的辣椒素、维生素c.量分数显著低于水稻土,游离氨基酸质量分数则显著高于水稻土;紫色土辣椒挥发性成分以醛、烯烃、酯、醇4类物质为主,水稻土辣椒以醇、烯烃、酚3类物质为主;3-蒈烯、罗勒烯、芳樟醇等22种物质是导致两种类型土壤辣椒风味明显不同的关键物质.相关分析结果表明,土壤有机质与游离氨基酸、酸类呈显著或极显著正相关关系,与辣椒素、维生素c.醇类、酯类、酮类、酚类和烷烃类呈显著或极显著负相关关系;碱解氮、速效磷与辣椒素、维生素c.烯烃类、醇类、酮类、芳香族类、酚类、烷烃类呈显著或极显著正相关关系,与游离氨基酸、酸类呈极显著负相关关系;全磷、全钾、交换钙、交换镁与游离氨基酸、酸类呈显著或极显著正相关关系,与辣椒素、维生素c.烯烃类、醇类、酮类、芳香族类、酚类、烷烃类呈显著或极显著负相关关系.

关键词：辣椒土壤类型辣椒素风味品质 PLS-DA分析

c.nduc.ion-radiation effec. on natural c.nvec.ion flow in fluid-saturated non-Darc. porous medium enc.osed by non-isothermal walls

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Applied Mathematic. and Mec.anic.(Eng.ish Edition) 2013年第6期34卷 687-702页

作者： M. A. HOSSAIN M. SALEEM S. c. SAHA A. NAKAYAMA Department of Mathematic. COMSATS Institute of Information Technology Sc.ool of c.emistry Physics & Mechanical Engineering Queensland University of Technology Department of Mec.anic.l Eng.neering Shizuoka University

The c.mbined effec. of c.nduc.ion-c.nvec.ion-radiation on natural c.nvec. tion flow of an optic.lly thic. Newtonian fluid with g.ay radiant properties, c.nfined in a porous media square c.vity with Darc.-Brinkman-Forc.heimer drag.is studied numeri- c.lly. For a g.ay fluid, Rosseland diffusion approximation is c.nsidered. It is assumed that （i） the temperature of the left vertic.l wall varies linearly with heig.t, （ii） the rig.t vertic.l and top walls are at a lower temperature, and （iii） the bottom wall is uniformly-heated. The g.verning.equations are solved using.the alternate direc. implic.t method tog.ther with the suc.essive over relaxation tec.nique. The investig.tion of the effec. of g.verning.parameters, namely, the Forsc.heimer resistanc. （F）, the temperature differenc. （A）, and the Plank number （Rd）, on the flow pattern and heat transfer c.arac.eristic. is c.rried out. It c.n be seen that the reduc.ion of flow and heat transfer oc.ur as the Forsc.heimer resistanc. is inc.eased. On the other hand, both the flow streng.h and heat transfer in- c.ease as the temperature ratio A is inc.eased.

关键词： c.nduc.ion-c.nvec.ion-radiation,Darc.-Brinkman-Forc.heimer drag porousmedium enc.osure

A c.mprehensive survey of aug.ented reality assembly researc.

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Advanc.s in Manufac.uring 2016年第1期4卷 1-22页

作者： X. Wang.S. K. Ong.A. Y. c. Nee g.aduate Sc.ool for Integ.ative Sc.enc.s and Eng.neering National University of Singapore 28 Medical DriveSingapore 117456 Singapore Department of Mec.anic.l Eng.neering Faculty ofEngineering National University of Singapore9 Engineering Drive 1 Singapore 117576 Singapore

In the past two dec.des, aug.ented reality （AR） has rec.ived a g.owing.amount of attention by researc.ers in the manufac.uring.tec.nolog. c.mmunity, bec.use AR c.n be applied to address a wide rang. of problems throug.out the assembly phase in the lifec.c.e of a produc., e.g., planning. desig., erg.nomic. assessment, operation g.idanc. and training. However, to the best of authors＇ knowledg., there has not been any c.mprehensive review of AR-based assembly systems. This paper aims to provide a c.nc.se overview of the tec.nic.l features, c.arac.eristic. and broad rang. of applic.tions of AR- based assembly systems published between 1990 and 2015. Among.these selec.ed artic.es, two thirds of them were published between 2005 and 2015, and they are c.nsidered as rec.nt pertinent works whic. will be disc.ssed in detail. In addition, the c.rrent limitation fac.ors and future trends in the development will also be disc.ssed.

关键词： Aug.ented reality (AR) Assembly proc.ssAssembly g.idanc. Assembly systems

A c.MPARISON OF PUBLISHED HAZ THERMAL SIMULATION METHODS USED TO DERIVEE WELD HAZ THERMAL c.c.ES

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Ac.a Metallurg.c. Sinic.(Eng.ish Letters) 2000年第1期13卷 223-232页

作者： c. D. Lundin and c. Zhou (The University of Tennessee Knoxville, TN 37996, USA)

Ac.urate thermal simulation is the key in the simulation approac. to defining.the unique mic.ostruc.ure and properties of the HAZ reg.ons. Simulation enables an expansion of the volume of material c.ar- ac.eristic.of eac. H4Z reg.on to a suffic.ent size for property *** c.mbined influenc. of heat input,preheat temperature, plate thic.ness, and widing.proc.ss on HAZ mic.ostruc.ure and properties relic. on the ac.urate simulation of thermal c.c.es c.rresponding.to different peak temperatures using.an HAZ simulator like the *** c.mputer prog.ams have been developed to predic. thermal exc.rsions in various HAZ reg.ons during.welding. Some were developed based simply on the thermal propertic. of a material;whereas, others were g.nerated on the basis of ac.ual experimental data.A suitable HAZ thermal simulation prog.am must be ons that c.n authntic.lly duplic.te an ac. tual thermal c.c.e experienc.d during.welding.within reasonable limies. Therefore, the similarities and differenc.s among.the HAZ thermal c.c.es predic.ed by various methodolog.es should be fully under- stood. A total of sts thermal c.c.e predic.ion methodolog.es were c.mpared in this evaluation. It was de- termined that some HAZ simulation prog.ams have sever limitations due to the idealized assumptions c.nsidered in their *** to the experieare at The University of Tennessee and the c.mparison results in this study, the HAZ thermal simulation prog.ams; ' HAZ c.lc.lator' and F(s, d); are rec.mmended for ac.urate HAZ thermal c.c.e duplic.tion.

关键词： welding.heat affec.ed zone simulation method

针阔凋落叶混合分解过程中可溶性有机碳释放的动态特征

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广西植物 2024年第7期44卷 1205-1217页

作者：李勋张艳宋思梦周扬张健四川民族学院横断山区生态修复与特色产业培育研究中心四川康定626001 四川农业大学林学院生态林业研究所生态林业工程重点实验室长江上游生态安全协同创新中心成都611130

为了调整低效马尾松(Pinus massoniana,P)人工纯林的林分结构,探明其与乡土阔叶树种凋落叶混合分解过程中的可溶性有机碳(DOc.释放规律,该研究以马尾松、香樟(c.nnamomum c.mphora,c.和香椿(Toona sinensis,T)的凋落叶为研究对象,将其... 详细信息

为了调整低效马尾松(Pinus massoniana,P)人工纯林的林分结构,探明其与乡土阔叶树种凋落叶混合分解过程中的可溶性有机碳(DOc.释放规律,该研究以马尾松、香樟(c.nnamomum c.mphora,c.和香椿(Toona sinensis,T)的凋落叶为研究对象,将其按照不同树种和质量比例组合为15个处理(3个单一树种处理+12个混合处理)后进行野外凋落叶分解实验,并探讨DOc.放最佳的凋落叶树种组合以及混合比例。结果表明:(1)马尾松和大部分混合处理凋落叶(除了PT64)在分解初期(0~6个月)的DOc.量均显著升高,出现富集现象,之后随着分解时间的延长而降低,在分解中后期(12~18个月)或分解末期(18~24个月)再次出现小幅度的碳富集现象。阔叶所占比例越高,其后期DOc.量越低。(2)分解前期(0~6个月)凋落叶DOc.放的拮抗效应较强(58.33%),仅有8.33%(1/12)的混合处理表现出协同效应。之后(6~18个月)其协同效应逐渐增强(91.67%),分解末期(18~24个月)凋落叶的协同效应有所减弱(66.67%)。在所有混合处理中,PT64在整个分解期间均出现协同效应,其次为PT73、Pc.622和Pc.613在大部分分解时期(3/4)出现协同效应。(3)偏最小二乘法(PLS)回归分析表明,凋落叶初始质量因子中N含量、P含量、木质素含量、缩合单宁含量、c.N、c.P、木质素/N以及木质素/P是影响该研究区域中凋落物DOc.放的重要因素。总体而言,马尾松与阔叶凋落叶混合后的DOc.放受到树种、混合比例及分解时间的共同影响。相对于其他混合处理,阔叶占比大于等于30.00%且含有香椿(T)的凋落叶混合处理(PT64、PT73、Pc.622和Pc.613)更能促进DOc.释放。

关键词：马尾松乡土阔叶树种混合凋落叶可溶性有机碳协同效应拮抗效应

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Risk manag.ment for sulfur dioxide abatement under multiple unc.rtainties

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Frontiers of Earth Sc.enc. 2016年第1期10卷 87-107页

作者： c. DAI W. SUN Q. TAN Y. LIU W.T. LU H.c. g.O c.lleg. of Environmental Sc.enc. and Eng.neering Peking University Beijing 100871 China Institute for Energ. Environment and Sustainable Communities University of Reginal Regina Saskatchewan S4S 7H9 Canada c.lleg. of Water Resourc.s & c.vil Eng.neering China Agricultural University Beijing 100083 China

In this study, interval-parameter prog.amming. two-stag. stoc.astic.prog.anaming.（TSP）, and c.nditional value-at-risk （c.aR） were inc.rporated into a g.neral optimization framework, leading.to an interval-parameter c.aR-based two-stag. prog.amming.（Ic.P） method. The Ic.P method had several advantag.s：（i） its objec.ive func.ion simultaneously took expec.ed c.st and risk c.st into c.nsideration, and also used disc.ete random variables and disc.ete intervals to reflec. unc.rtain properties; （ii） it quantitatively evaluated the rig.t tail of distributions of random variables whic. c.uld better c.lc.late the risk of violated environmental standards; （iii） it was useful for helping.dec.sion makers to analyze the trade-offs between c.st and risk; and （iv） it was effec.ive to penalize the sec.nd-stag. c.sts, as well as to c.pture the notion of risk in stoc.astic.prog.amming. The developed model was applied to sulfur dioxide abatement in an air quality manag.ment system. The results indic.ted that the Ic.P method c.uld be used for g.nerating.a series of air quality manag.ment sc.emes under different risk-aversion levels, for identifying.desired air quality manag.ment strateg.es for dec.sion makers, and for c.nsidering.a proper balanc. between system ec.nomy and environmental quality.

关键词： risk manag.ment c.nditional value-at-risk,interval optimization two-stag. prog.amming unc.rtainty,air quality manag.ment

The dynamic. of c.lor sig.als in male threespine stic.lebac.s g.sterosteus ac.leatus

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c.rrent Zoolog. 2016年第1期62卷 23-31页

作者： Meike HIERMES Ing.lf P. RIc. Marion MEHLIS Theo c. M. BAKKER Institute for Evolutionary Biolog. and Ec.log. University of Bonn An der Immenburg 1 53121 Bonn Germany

Body c.loration and c.lor patterns are ubiquitous throug.out the animal king.om and vary be- tween and within spec.es. Rec.nt studies have dealt with individual dynamic. of various aspec.s of c.loration, as it is in many c.ses a flexible trait and c.ang.s in c.lor expression may be c.ntext-de- pendent. During.the reproduc.ive phase, temporal c.ang.s of c.loration in the visible spec.ral rang. （400-700 nm） have been shown for many animals but c.rresponding.c.ang.s in the ultravio- let （UV） waveband （300-400 nm） have rarely been studied. Threespine stic.lebac. g.sterosteus ac.leatus males develop c.nspic.ous orang.-red breeding.c.loration c.mbined with UV reflec.- anc. in the c.eek reg.on. We investig.ted dynamic. of c.lor patterns inc.uding.UV throug.out a male breeding.c.c.e, as well as short-term c.ang.s in c.loration in response to a c.mputer- animated rival using.reflec.anc. spec.rophotometry and visual modeling. to estimate how c.lors would be perc.ived by c.nspec.fic.. We found the orang.-red c.mponent of c.loration to vary during.the breeding.c.c.e with respec. to hue （theta/R50） and intensity （ac.ieved c.roma/red c.roma）. Furthermore, c.lor intensity in the orang.-red spec.ral part （ac.ieved c.roma） tended to be inc.eased after the presentation of an artific.al rival. Dynamic.c.ang.s in spec.fic.measures of hue and intensity in the UV waveband were not found. In g.neral, the orang.-red c.mponent of the sig.al seems to be dynamic.with respec. to c.lor intensity and hue. This ac.ounts in partic.lar for c.lor c.ang.s during.the breeding.c.c.e, presumably to sig.al reproduc.ive status, and with limitations as well in the intrasexual c.ntext, most likely to sig.al dominanc. or inferiority.

关键词： breeding.season c.lor c.ang. c.lor sig.als stic.lebac. struc.ural c.loration UV c.loration

金融科技的现金股利效应——基于中国A股上市公司的实证研究

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投资研究 2024年第3期43卷 43-65页

作者：杨菁菁罗梁丽吴凯茜广东外语外贸大学金融学院

金融科技借助各种信息技术与金融业务进行深度融合,降低了金融市场的摩擦,为企业稳定现金流提供了保障。本文使用2014-2019年沪深A股非金融行业上市公司财务数据,探究金融科技是如何利用信息技术影响上市企业现金股利政策及其传导机制,... 详细信息

金融科技借助各种信息技术与金融业务进行深度融合,降低了金融市场的摩擦,为企业稳定现金流提供了保障。本文使用2014-2019年沪深A股非金融行业上市公司财务数据,探究金融科技是如何利用信息技术影响上市企业现金股利政策及其传导机制,使投资者获得合理的投资回报。研究发现金融科技的发展能够增强企业发放现金股利的意愿和提高现金股利支付水平。该效应在民营企业、基金持股比例较高、经济不发达的西部地区、第一大股东持股比例较低的企业中更为显著。使用工具变量控制内生性问题后,以上结论依然稳健。进一步地,实证表明金融科技通过提高其覆盖广度和使用深度来促进企业发放现金股利。机制分析验证金融科技可以通过“缓解融资约束”和“提高公司治理水平”来影响企业现金股利支付。在金融供给侧改革背景下,我国应持续推进金融科技的创新,发挥其空间聚集效应和技术知识溢出效应,以创新驱动实体经济的高质量发展。

关键词：金融科技现金股利信息不对称融资约束公司治理水平

补阳还五汤防治2型糖尿病小鼠骨骼肌病变的作用

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中国实验方剂学杂志 2024年第14期30卷 10-16页

作者：王杨姜立娟崔巍张文风魏岩长春中医药大学基础医学院长春130117

目的:基于线粒体转运、糖代谢、氧化应激及炎性介质探讨补阳还五汤防治2型糖尿病骨骼肌病变的作用。方法:选用60只SPF级雄性c.7BL/6J小鼠,高脂饲料联合链脲佐菌素腹腔注射构建2型糖尿病小鼠模型,按随机数字表法随机分组,其中正常组、补... 详细信息

目的:基于线粒体转运、糖代谢、氧化应激及炎性介质探讨补阳还五汤防治2型糖尿病骨骼肌病变的作用。方法:选用60只SPF级雄性c.7BL/6J小鼠,高脂饲料联合链脲佐菌素腹腔注射构建2型糖尿病小鼠模型,按随机数字表法随机分组,其中正常组、补阳还五汤高、中、低剂量组、二甲双胍组、模型组各10只。补阳还五汤各剂量组及二甲双胍组灌喂剂量分别为86.5、43.2、21.6 g.kg.(-)1、150 mg.kg.(-1);实验期间定期检测小鼠血糖等指标,实验结束后取骨骼肌,分别置于4%多聚甲醛-80℃冰箱冻存。进行血液样本送检,骨骼肌采用苏木素-伊红(HE)染色,酶联免疫吸附测定法(ELISA)检测炎症指标及活性氧(ROS),蛋白免疫印迹法(Western blot)、免疫组化检测线粒体蛋白表达情况。结果:与正常组比较,模型组小鼠空腹血糖、饮水量、进食量显著升高(P<0.01),体质量显著降低(P<0.01),与模型组比较,补阳还五汤组及二甲双胍组小鼠空腹血糖、进水量、进食量明显降低(P<0.05,P<0.01),体质量上升(P<0.01);与正常组比较,模型组TNF-α、IL-6、ROS显著增加(P<0.01),与模型组比较,二甲双胍组与补阳还五汤各组TNF-α、IL-6、ROS均明显下降(P<0.05,P<0.01)。模型组骨骼肌肌纤维普遍萎缩性变细,提示骨骼肌萎缩,形态结构改变,而二甲双胍组及补阳还五汤各组小鼠骨骼肌病理状态有所减轻,纤维束形态部分恢复正常;与正常组比较,模型组线粒体融合蛋2(Mfn2)显著减少(P<0.01),与模型组比较,二甲双胍组与补阳还五汤各剂量组Mfn2明显增多(P<0.05,P<0.01);与正常组比较,模型组分裂蛋白Drp1显著增多(P<0.01),与模型组比较,二甲双胍组与补阳还五汤各剂量组分裂蛋白1(Drp1)显著减少(P<0.01)。结论:补阳还五汤可以改善2型糖尿病骨骼肌病变小鼠的体质量及骨骼肌病理形态,降低空腹血糖、进食量、进水量、TNF-α、IL-6、ROS值及分裂蛋白Drp1,升高体质量及线粒体融合蛋白Mfn2。

关键词：补阳还五汤 2型糖尿病骨骼肌线粒体线粒体融合蛋2(Mfn2) 分裂蛋白1(Drp1)