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国外农学（蚕业） 1993年第2期 6-14页

作者： s.s.gill 钱纪放

一、引言过去半个世纪发展起来的有机杀虫剂的应用,能给人类健康造成危害并能引起环境问题。因此,对害虫管理中应用替代策略的兴趣已经有了发展。开展苏芸金芽孢杆菌(Bt)

关键词：苏芸金杆菌内毒素

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2n卵细胞配子在甘蔗高贵化育种中的意义

甘蔗糖业 1986年第8期 50-54页

作者： sHRIPAD R.BHAT s.s.gill 程仲华

从遗传的角度观察2n 配子在甘蔗高贵化中的意义。计算第Ⅰ、Ⅱ次高贵化后代中由2n 配子造成的近交系数。讨论2n 配子对于甘蔗育种的意义。

关键词：甘蔗糖料作物割手密配子配偶子配子体热带种高贵种甘蔗育种卵细胞卵子

对Bs 5500附录G中圆筒形壳体由局部载荷引起的应力计算方法的几点意见

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化工设备与管道 1985年第3期 8-18页

作者： R.Bedri R.D.Mcleish s.s.gill 玉增凤

Bs 5500附录 G 中的计算圆筒形壳体矩形区域上径向力和力矩引起应力的方法十分复杂,试用简化计算的参数测量图后,表明:(i)附录 G 方法的可靠性要求几何参数所作的限制,致使该方法的使用范围受到许多限制。(ii)在周向力矩作用引起应力的... 详细信息

Bs 5500附录 G 中的计算圆筒形壳体矩形区域上径向力和力矩引起应力的方法十分复杂,试用简化计算的参数测量图后,表明:(i)附录 G 方法的可靠性要求几何参数所作的限制,致使该方法的使用范围受到许多限制。(ii)在周向力矩作用引起应力的计算方法中,因忽略第二承载区上载荷引起的应力,而得出不正常的结果。(iii)在纵向力矩载荷条件下,当矩形区域偏离容器长度中点时,附录 G 要求计算两个承载区

关键词：附录符号书籍结构力矩载荷承载区周向应力计算

玻璃纤维树脂增强压力容器的三心圆封头的强度和变形——环半径/圆筒直径比对于球半径与圆筒直径相等的封头之影响

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国外固体火箭技术 1984年第4期 63-87页

作者： D.C.Barton P.D.soden s.s.gill 廉茂林

我们做了6台带有三心圆封头的玻璃纤维树脂增强圆筒压力容器的破坏试验。各容器的标称厚度与直径之比为0.01,封头的球半径和圆筒的直径都是1米。环半径有三种尺寸,分别为0.29、0.19和0.1米,相对应的封头高度分别是0.32、0.25和0.19米(... 详细信息

我们做了6台带有三心圆封头的玻璃纤维树脂增强圆筒压力容器的破坏试验。各容器的标称厚度与直径之比为0.01,封头的球半径和圆筒的直径都是1米。环半径有三种尺寸,分别为0.29、0.19和0.1米,相对应的封头高度分别是0.32、0.25和0.19米(每种尺寸的容器各做了两台试验)。把试验结果同现行的英国国家设计标准(Bs4994)以及根据弹性应力分析运用计算机所求得的预测值(BOsOR4),进行了比较,完全证明了最大应力和应变是随环半径的减小而增加的。另外还发现:由于三心圆封头玻璃纤维树脂增强圆筒压力容器(GRP)的高弹应变,封头在压力作用下几何形状的变化对极限强度有很大的影响,再加上壁厚的局部增加,使得封头有所加强,以致在所试验的6台容器中,仅有3台的破坏发生在三心圆封头上。

关键词：压力容器封头三心圆玻璃纤维人造无机纤维树脂

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甘蔗(野生蔗杂种)宿根能力基因型的筛选

甘蔗糖业 1984年第7期 53-55页

作者： B.K.Tripathi s.s.gill G.P.Misra s.Lal 关中秀

在印度 Lucknow 用74个 Co 品系甘蔗(1968—1974年),81个外国品种和来自7个双亲杂交的2824个不同无性系评价其宿根能力。在 Co 品系和外国品种宿根蔗测试中,Co7321优于 Co1148。在双亲杂交无性系的新植和宿根研究中,选出7个 Colk 品种,... 详细信息

在印度 Lucknow 用74个 Co 品系甘蔗(1968—1974年),81个外国品种和来自7个双亲杂交的2824个不同无性系评价其宿根能力。在 Co 品系和外国品种宿根蔗测试中,Co7321优于 Co1148。在双亲杂交无性系的新植和宿根研究中,选出7个 Colk 品种,也就是 Colk7701、Colk7702、Colk7707、Colk7708、Colk7710。Colk7701在新植蔗中显著优于 Co1148,而其宿根蔗的产量则相等,但蔗糖的百分率无论在新植蔗及宿根蔗中,Colk7701均高于 Co1148。对于良好宿根能力的选择,建议在早期无性系选择的宿根蔗中进行,以便获得更加理想的无性系。本文还进一步提出了在宿根中通过增加株丛间距离和移植较密的株丛补足其缺株数,并通过发挥其自身调节能力而增加产量。

关键词：甘蔗品种无性系选择 Co 双亲人工选择宿根蔗宿根能力新植蔗遗传型基因型

Effect of Eu3+,Bi3+,and Li+ doping on luminescent property of GdNbO4

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Journal of Rare Earths 2024年第1期42卷 66-75页

作者： s.W.Wi Y.s.Lee Department of Physics and Integrative Institute of Basic sciences Soongsil University

We investigated the emission properties of Eu3+-doped GdNbO4-based oxide phosphors,aiming at improving the Eu3+emission by codoping of Bi3+and Li+.Eu3+singly doped,Eu3+and Bi3+doubly doped,and Eu3+,Bi3+,and Li+triply doped GdNbO4were prepared using a high-temperature solid-state reaction *** red-orange emissions from Eu3+in the singly doped samples are significantly improved by the codoping of Bi3+,mainly due to the energy transfer from Bi3+to Eu3+.The additional codoping of Li+is found to increase the Eu3+emission *** improvement might be attributed to the increase in the photoluminescent quantum yield originating from larger grain sizes and better crystallinity.A detailed analysis of the X-ray diffraction pattern and the asymmetric ratio estimated from the photoluminescence spectra show that the local lattice environment around Eu3+in GdNbO4does not change significantly with the codoping of Bi3+and Li+.Our results indicate that Li+doping is a promising way to improve the emission properties of rare-earth ion-doped GdNbO4phosphors.

关键词： Eu 3+ GdNbO 4 Codoping of Li + Photoluminescence sensitizer Rare earths

First evidence for chiral wobbling of triaxial nuclei

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Nuclear science and Techniques 2024年第7期35卷 4-7页

作者： s.Frauendorf Department of Physics and Astronomy University of Notre DameNotre DameIN 46556USA

Chirality(Greek“handiness”)is a property of many com-plex *** molecules exist in two forms,one being the mirror image of the *** for our hands,it is impossible to make the images identical by a suitable *** two forms are called left-handed and *** have the same binding energy,because the electro-magnetic interaction,which holds the molecule together,does not change under a *** properties that are insensitive to the geometry are also the *** different geometry is the reason why the left-handed form turns the polarization plane of transmitted light in one direction by some angle while the right-handed form turns it in the oppo-site direction by the same ***,the geometrical differences between the two species may have other *** two species of the carvon molecule shown in Fig.1 taste quite differently.

关键词： turns Chiral mirror

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Tribological behavior of lubricant-impregnated porous polyimide

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Friction 2024年第4期12卷 711-725页

作者： Jinbang LI Ningning ZHOU Janet s.s.WONG school of Mechanical Engineering and Mechanics Ningbo UniversityNingbo 315211China Beijing Key Laboratory of Long-life Technology of Precise Rotation and Transmission Mechanisms Beijing Institute of Control EngineeringBeijing 100029China Department of Mechanical Engineering Imperial College LondonLondon SW72AZUK

Porous materials impregnated with lubricants can be used in conditions where limited lubricant is *** this work,three porous polyimides(PPI)with different densities were ***(PAO)impregnated PPI(iPPI)discs were rubbed against steel and sapphire *** operando observations of the iPPI-sapphire contacts show that oil is released under an applied load,forming a meniscus around *** at the outlet is created at high sliding *** amount of released oil increases with increasing PPI *** moduli,E*,estimated based on the actual contact size show that trapped oil in iPPIs contributes to load *** higher speeds,tribological rehydration of the contact occurs in low density iPPI,with that E*rises with *** high density PPIs,high speeds give a constantly high E*which is limited by the viscoelastic properties of the PPI network and possibly the rate of oil *** of iPPI-steel contacts is governed by the mechanical properties of the PPI,the flow of the lubricant,and the roughness of the PPI *** low-and medium-density(highly porous,high roughness)PPIs,large amount of oil is released,and lubrication is mainly via lubricant restricted in the contact in the pores and possibly tribological *** high density(low porosity)PPI,with lower roughness,hydrodynamic lubrication is achieved which gives the lowest *** results show that polymeric porous materials for effective lubrication require the optimization of its surface roughness,stiffness,oil flow,and oil retentions.

关键词： polyimide porous material friction mechanism polymer limited lubrication

Enhancing fatigue performance of AZ31 magnesium alloy components fabricated by cold metal transfer-based wire arc directed energy deposition through LPB

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Journal of Magnesium and Alloys 2024年第4期12卷 1638-1662页

作者： shambhu Kumar Manjhi srikanth Bontha A.s.s.Balan Department of Mechanical Engineering National Institute of Technology KarnatakaSurathkalSrinivasanagarMangaloreKarnataka 575025India

Cold Metal Transfer-Based Wire Arc Directed Energy Deposition(CMT-WA-DED)presents a promising avenue for the rapid fabrication of components crucial to automotive,shipbuilding,and aerospace ***,the susceptibility to fatigue of CMT-WA-DED-produced AZ31 Mg alloy components has impeded their widespread adoption for critical load-bearing *** this study,a comprehensive investigation into the fatigue behaviour of WA-DED-fabricated AZ31 Mg alloy has been carried out and compared to commercially available wrought AZ31 *** findings indicate that the as-deposited parts exhibit a lower fatigue life than wrought Mg alloy,primarily due to poor surface finish,tensile residual stress,porosity,and coarse grain microstructure inherent in the WA-DED *** Plasticity Burnishing(LPB)treatment is applied to mitigate these issues,which induce significant plastic deformation on the *** treatment resulted in a remarkable improvement of fatigue life by 42%,accompanied by a reduction in surface roughness,grain refinement and enhancement of compressive residual stress ***,during cyclic deformation,WA-DED specimens exhibited higher plasticity and dislocation density compared to both wrought and WA-DED+LPB specimens.A higher fraction of Low Angle Grain Boundaries(LAGBs)in WA-DED specimens contributed to multiple crack initiation sites and convoluted crack paths,ultimately leading to premature *** contrast,wrought and WA-DED+LPB specimens displayed a higher percentage of High Angle Grain Boundaries(HAGBs),which hindered dislocation movement and resulted in fewer crack initiation sites and less complex crack paths,thereby extending fatigue *** findings underscore the effectiveness of LPB as a post-processing technique to enhance the fatigue performance of WA-DED-fabricated AZ31 Mg alloy *** study highlights the importance of LPB surface treatment on AZ31 Mg components produced by CMT-WA-DED to remove surface d

关键词： Wire arc additive manufacturing AZ31 Mg alloy Low plasticity burnishing Low cycle fatigue test strain amplitude

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Applying Machine Learning Approach to Explore Childhood Circumstances and self-Rated Health in Old Age-China and the Us,2020-2021

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China CDC weekly 2024年第11期6卷 213-218,I0008-I0013页

作者： shutong Huo Derek Feng Thomas M.gill Xi Chen Department of Health Society&BehaviorPublic HealthUniversity of CaliforniaIrvineCAUSA Department of statistics and Data science Yale UniversityNew HavenCTUS Department of Internal Medicine Yale School of MedicineNew HavenCTUS Department of Health Policy and Management Yale School of Public HealthNew HavenCTUS Department of Economics Yale UniversityNew HavenCTUS.

Introduction:Childhood circumstances impact senior health,prompting the introduction of machine learning methods to assess their individual and collective contributions to senior ***:Using health and retirement study(HRs)and China Health and Retirement Longitudinal study(CHARLs),we analyzed 2,434 American and 5,612 Chinese participants aged 60 and *** inference trees and forests were employed to estimate the influence of childhood circumstances on self-rated health(sRH).Results:The conventional method estimated higher inequality of opportunity(IOP)values in both China(0.039,accounting for 22.67%of the total Gini coefficient 0.172)and the Us(0.067,accounting for 35.08%of the total Gini coefficient 0.191).In contrast,the conditional inference tree yielded lower estimates(China:0.022,accounting for 12.79%of 0.172;Us:0.044,accounting for 23.04%of 0.191),as did the forest(China:0.035,accounting for 20.35%of 0.172;Us:0.054,accounting for 28.27%of 0.191).Childhood health,financial status,and regional differences were key determinants of senior *** conditional inference forest consistently outperformed others in predictive accuracy,as demonstrated by lower out-of-sample mean squared error(MsE).Discussion:The findings emphasize the need for early-life interventions to promote health equity in aging *** learning showcases the potential in identifying contributing factors.

关键词： collective inequality estimates