期刊文献+
共找到74篇文章
< 1 2 4 >
每页显示 20 50 100
Constraining the colored cc energy loss from J/Ψ production in p-A collisions 被引量:2
1
作者 Li-Hua Song Lin-Wan Yan Ying Liu 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第11期205-213,共9页
Considering the volatility of the propagation path for charmonium passing across the nuclear target in J/ψ formation from p-A collisions, the charmonium energy loss is investigated using Salgado-Wiedemann quenching w... Considering the volatility of the propagation path for charmonium passing across the nuclear target in J/ψ formation from p-A collisions, the charmonium energy loss is investigated using Salgado-Wiedemann quenching weights. A successful description regarding J/ψsuppression of R_(w(Fe)/Be)(x_F) from the E866 experiment for 0.2 <x_F<0.65 gives the transport coefficient q = 0.29 ± 0.07 GeV^2/fm for the colored cc energy loss.The calculated result indicates that radiative energy loss of a parton should be independent of its mass at high energy.The calculations are further compared to LHC and RHIC measurements. 展开更多
关键词 jproduction Energy loss CHARM QUARK GLUON
下载PDF
J/ψ production in p+p and p+Pb collisions at ultrarelativistic energies 被引量:2
2
作者 Hong-Min Wang Zhao-Yu Hou +1 位作者 Xiu-Ting Wang Xian-Jing Sun 《Nuclear Science and Techniques》 SCIE CAS CSCD 2018年第8期179-185,共7页
The production of J/ψ mesons in p+p and p+Pb collisions is studied in the framework of color-glass condensate together with a simple color evaporation model.Considering the nuclear effects with the Glauber–Gribov ap... The production of J/ψ mesons in p+p and p+Pb collisions is studied in the framework of color-glass condensate together with a simple color evaporation model.Considering the nuclear effects with the Glauber–Gribov approach,we calculate the cross section and the nuclear modification factor of forward J/ψ production in p+Pb collisions at s^(1/2) 5:02 TeV.Then,the backward J/ψ production in p+Pb collisions at s^(1/2) 8:16 Te V is also analyzed.In our calculation,the phenomenology KLRAd S/CFT model and the rc BK approach,which are valid at a small x,are used to calculate the three-point function.It is shown that the theoretical results fit well with the experimental data from ALICE and LHCb. 展开更多
关键词 碰撞 生产 GLAUBER 精力 j 修正因素 冷凝物 现象学
下载PDF
Nuclear Effect on Gluon Distribution Function and Associate Production of J/Ψ and y with Large P_T in High Energy p-Fe Collision
3
作者 Zhang Shu~2 He Zhe-min~(1,2) Peng Hong-an~(1,3) Duan Chun-gui~21 CCAST(World Laboratory)P.O.Box 8730,Biejing 1000802 Physics Department,Hebei Normal University,Shijiazhuang,0500163 Physics Department,Peking University,Beijing 100871 《Chinese journal of nuclear physics》 1995年第3期205-208,共4页
With three theoretical models of nuclear effects on gluon distribution functions,the differentialcross sections and the total cross sections for associate production of J/ψ and γ with large P_T in high energyp-Fe co... With three theoretical models of nuclear effects on gluon distribution functions,the differentialcross sections and the total cross sections for associate production of J/ψ and γ with large P_T in high energyp-Fe collisions are calculated. 展开更多
关键词 GLUON distribution FUNCTION Nuclear effect j production
下载PDF
J/ψ and T Photoproduction at LHC
4
作者 Li Yunde XU Xiaomei Liu Lianshou 《Chinese journal of nuclear physics》 1997年第3期129-132,共4页
Hard photoproduction of J/ψ and T at large hadron collider(LHC)Pb-Pb collisionswith CMS energy 6300 GeV/u is discussed in the process Pb+Pb→Pb+J/ψ+X with threetypes of equivalent photon spectrum functions.It turns ... Hard photoproduction of J/ψ and T at large hadron collider(LHC)Pb-Pb collisionswith CMS energy 6300 GeV/u is discussed in the process Pb+Pb→Pb+J/ψ+X with threetypes of equivalent photon spectrum functions.It turns out that the hard photoproductionprocesses can be used to probe several important problems such as the gluon distribution in thenucleus,gluon and heavy q.uark fragmentation of J/ψ,et al.In addition,the process alsoprovides a new way of testing the EMC effects. 展开更多
关键词 Photoproduction process j and T production Equivalent photon spectrum
下载PDF
Circular L(j,k)-labeling numbers of trees and products of graphs 被引量:3
5
作者 吴琼 林文松 《Journal of Southeast University(English Edition)》 EI CAS 2010年第1期142-145,共4页
Let j, k and m be three positive integers, a circular m-L(j, k)-labeling of a graph G is a mapping f: V(G)→{0, 1, …, m-1}such that f(u)-f(v)m≥j if u and v are adjacent, and f(u)-f(v)m≥k if u and v are... Let j, k and m be three positive integers, a circular m-L(j, k)-labeling of a graph G is a mapping f: V(G)→{0, 1, …, m-1}such that f(u)-f(v)m≥j if u and v are adjacent, and f(u)-f(v)m≥k if u and v are at distance two,where a-bm=min{a-b,m-a-b}. The minimum m such that there exists a circular m-L(j, k)-labeling of G is called the circular L(j, k)-labeling number of G and is denoted by σj, k(G). For any two positive integers j and k with j≤k,the circular L(j, k)-labeling numbers of trees, the Cartesian product and the direct product of two complete graphs are determined. 展开更多
关键词 circular L(j k)-labeling number TREE Cartesian product of graphs direct product of graphs
下载PDF
Research on the J2EE-based product database management system 被引量:3
6
作者 林琳 姚郁 钟诗胜 《Journal of Harbin Institute of Technology(New Series)》 EI CAS 2007年第1期106-113,共8页
The basic frame and the design idea of J2EE-based Product Data Management (PDM) system are presented. This paper adopts the technology of Object-Oriented to realize the database design and builds the information model... The basic frame and the design idea of J2EE-based Product Data Management (PDM) system are presented. This paper adopts the technology of Object-Oriented to realize the database design and builds the information model of this PDM system. The integration key technology of PDM and CAD systems are discussed, the isomerous interface characteristics between CAD and PDM systems are analyzed, and finally, the integration mode of the PDM and CAD systems is given. Using these technologies, the integration of PDM and CAD systems is realized and the consistence of data in PDM and CAD systems is kept. Finally, the Product Data Management system is developed, which has been tested on development process of the hydraulic generator. The running process is stable and safety. 展开更多
关键词 product data management (PDM) system j2EE OBjECT-ORIENTED
下载PDF
‘Partly'globalized networks and driving mechanism in resource-based state-owned enterprises:A case study of J Group 被引量:1
7
作者 Jing Xu Yongchun Yang +1 位作者 Yongjiao Zhang Shan Man 《Geography and Sustainability》 CSCD 2024年第1期77-88,共12页
In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in th... In the context of economic globalization,while multinational enterprises from developed countries occupy a high-end position in the global value chain,enterprises from developing countries are often marginalized in the world market.In China,resource-based state-owned enterprises(SOEs)are tasked with the mission of safeguarding resource security,and their internationalization development ideas and strategic deployment are significantly and fundamentally different from those of other non-state-owned enterprises and large multinational corporations.This study provides ideas for the globalization policies of enterprises in developing countries.We consider J Group in western China as a case and discuss its productive investment and global production network development from 2010 to 2019.We found that J Group was‘Partly'globalized,and there are multiple core nodes with the characteristics of centralized and decentralized coexistence in the production network;in addition,the overall layout centre shifted to Southeast Asia and China;however,its global production was restricted by the enterprise's investment security considerations,support and restrictions of the home country,political security risk of the host country,and sanctions from the West.These findings provide insights for future research:under the wave of anti-globalization and'internal circulation as the main body',resource SOEs should consider the potential risk of investment,especially keeping the middle and downstream industrial chain in China as much as possible. 展开更多
关键词 Global production networks Global value chain productive investment Resource SOEs j Group ‘Partly'globalized
下载PDF
J亚群禽白血病对商品蛋鸡生产性能影响的研究 被引量:12
8
作者 李晓华 王海旺 +5 位作者 袁正东 袁玉仲 杨书展 张小丽 崔治中 佘锐萍 《中国家禽》 北大核心 2012年第2期9-13,17,共6页
试验对一个大型蛋用鸡场的不同种源商品代蛋鸡群的J亚群禽白血病毒(ALV-J)感染状态与鸡群总死淘率、肿瘤发生率、生产性能的相关性进行了研究。结果表明,从ALV-J感染的父母代鸡场引进的商品代蛋鸡,从性成熟开始不仅整个鸡群的ALV—... 试验对一个大型蛋用鸡场的不同种源商品代蛋鸡群的J亚群禽白血病毒(ALV-J)感染状态与鸡群总死淘率、肿瘤发生率、生产性能的相关性进行了研究。结果表明,从ALV-J感染的父母代鸡场引进的商品代蛋鸡,从性成熟开始不仅整个鸡群的ALV—J抗体阳性率较高,而且总死淘率显著高于生产标准,主要是由肿瘤/血管瘤引起。这些鸡群的产蛋性能也显著低于生产标准。从2009年下半年起,选择无ALV-J感染的父母代种鸡场作为种源,引进19批约190万只雏鸡,分别在1~21周龄抽检血清ALV-J抗体,均为阴性,且不再有肿瘤/血管瘤发生。两年多来,这些无ALV-J感染蛋鸡群的总死淘率不仅比ALV-J感染鸡群降低8.34%,也显著低于生产手册的规定,产蛋率及产蛋高峰持续期均显著高于生产标准。临床和试验观测表明,种鸡感染ALV-J能显著影响商品代蛋鸡的生产性能,选择无ALV-J感染的种源是规模化养鸡场生物安全的最重要措施之一。 展开更多
关键词 j亚群鸡白血病 蛋鸡 生产性能 种源
下载PDF
禽白血病病毒J亚群感染对五华鸡生产性能和免疫性能的影响 被引量:13
9
作者 张丹俊 戴银 +5 位作者 赵瑞宏 胡晓苗 夏松林 盛昌树 杨文超 钟国发 《中国畜牧兽医》 CAS 北大核心 2012年第2期141-144,共4页
为了解禽白血病病毒J-亚群(ALV-J)感染对安徽省优良地方品种鸡—五华鸡生产性能和免疫性能的影响,在对五华鸡开展ALV-J血清学感染检测调研的基础上,对进入产蛋高峰期的五华鸡ALV-J血清阳性鸡群和阴性鸡群开展了为期18周的试验对比观察... 为了解禽白血病病毒J-亚群(ALV-J)感染对安徽省优良地方品种鸡—五华鸡生产性能和免疫性能的影响,在对五华鸡开展ALV-J血清学感染检测调研的基础上,对进入产蛋高峰期的五华鸡ALV-J血清阳性鸡群和阴性鸡群开展了为期18周的试验对比观察研究。结果表明,ALV-J血清阳性(感染或曾经感染)对五华鸡没有造成明显的发病和死亡增高现象;对鸡群新城疫(ND)、禽流感H5和H9疫苗的免疫效果没有呈现明显抑制;但对鸡群的产蛋率和平均蛋重会造成一定程度的下降(对照组平均产蛋率和蛋重分别为56%和0.055kg,而试验组为53.37%和0.051kg),料蛋比有一定程度的上升(对照组的料蛋比为3.49∶1,试验组为3.92∶1)。目前ALV-J感染虽然不会造成五华鸡明显的发病、死亡及免疫抑制,但可造成明显的生产性能下降和饲养成本的提高,必须引起高度重视,应及早开展原种鸡的ALV-J净化工作。 展开更多
关键词 五华鸡 j亚群禽白血病 生产性能 免疫性能
下载PDF
中美林产品贸易的J曲线验证 被引量:1
10
作者 耿利敏 沈文星 《林业经济》 北大核心 2014年第7期72-78,共7页
基于ARDL—ECM模型,文章以1990-2011年的中美林产品贸易数据,从汇率水平和汇率波动水平两个维度实证考察人民币汇率变动对中美林产品贸易的影响。结果表明,人民币升值在短期和长期内均对中美林产品贸易平衡有负面影响,但并不存在明... 基于ARDL—ECM模型,文章以1990-2011年的中美林产品贸易数据,从汇率水平和汇率波动水平两个维度实证考察人民币汇率变动对中美林产品贸易的影响。结果表明,人民币升值在短期和长期内均对中美林产品贸易平衡有负面影响,但并不存在明显的反J曲线效应,而汇率变动性风险的影响并不显著,这一研究结果值得政策制定部门对我国林产品贸易尤其是进口贸易的刚性需求重点关注,并慎重考虑林产品贸易战略的长远规划。 展开更多
关键词 j曲线效应 中美林产品贸易 ARDL-ECM模型
下载PDF
J酸的合成及其在直接染料活性染料中的应用 被引量:1
11
作者 孙桂春 《染整技术》 CAS 2012年第8期30-36,共7页
本文论述了J酸的合成方法,探讨了J酸制备过程中副产物Y酸的生成过程及其控制方法。根据《世界染料品种-2005》公开的染料品种结构,对于J酸及其衍生物在直接染料和活性染料中的使用情况做了分析。
关键词 j 副产物 直接染料 活性染料
下载PDF
JIT在苏南中小型电子制造企业深入应用的探讨 被引量:1
12
作者 金青 朱惠芳 +2 位作者 彭伏期 甘信华 丁兆国 《中国制造业信息化(学术版)》 2010年第1期29-33,共5页
阐述了JIT生产方式对苏南地区中小型电子制造企业的适宜性,以及苏南中小企业推行JIT生产方式存在的优势;提出了将JIT方式深入应用的3个方向,即瓶颈环节"准时物料供应"的解决方案,JIT生产系统的整体架构而不是仅仅只是"... 阐述了JIT生产方式对苏南地区中小型电子制造企业的适宜性,以及苏南中小企业推行JIT生产方式存在的优势;提出了将JIT方式深入应用的3个方向,即瓶颈环节"准时物料供应"的解决方案,JIT生产系统的整体架构而不是仅仅只是"看板系统",以及深入推行的实施手段。 展开更多
关键词 jIT生产方式(准时制生产方式) 中小企业 电子制造业 苏南地区 生产方式
下载PDF
基于信息化的JIT研究 被引量:4
13
作者 蒋海青 《中国制造业信息化(学术版)》 2008年第5期10-11,16,共3页
介绍了传统JIT的特点及JIT信息化的必要性,提出了进行JIT信息化的实现方法,并通过案例进行分析、应用,得到了很好的效果,为企业成功实现信息化管理、提高生产效率指出了一种新方法。
关键词 jIT 精益生产 信息化
下载PDF
J-PARC离子源多峰离子源三维数值模拟
14
作者 杨超 刘成安 《核聚变与等离子体物理》 CAS CSCD 北大核心 2014年第1期22-26,共5页
研究了矩形永磁体的理论计算方法,深入剖析了PIC-MCC处理算法,在粒子模拟软件平台下研制了全三维PIC-MCC模拟算法,并采用该算法数值研究了J-PARC多峰离子源放电特性,分析了J-PARC离子源电子能量沉积过程和体积产生机制,讨论了该离子源... 研究了矩形永磁体的理论计算方法,深入剖析了PIC-MCC处理算法,在粒子模拟软件平台下研制了全三维PIC-MCC模拟算法,并采用该算法数值研究了J-PARC多峰离子源放电特性,分析了J-PARC离子源电子能量沉积过程和体积产生机制,讨论了该离子源在光学特性和设计思路上的优势。结果显示:该离子源能产生空间均匀的负氢离子离子束,且体积负氢离子产生效率较高。 展开更多
关键词 j-PARC多峰离子源 体积产生 空间均匀性
下载PDF
环境胁迫对东方伊萨酵母FJ-J-3产乙醇的影响
15
作者 姚淑敏 郭倩 +3 位作者 王萍 陈珊 宋晴晴 徐凯峰 《中国酿造》 CAS 北大核心 2019年第1期125-128,共4页
该研究以东方伊萨酵母(Issatchenkia orientalis)FJ-J-3为研究对象,利用分光光度计法和气相色谱(GC)法测定其在不同pH和不同Na_2SO_4含量胁迫下的生长状况和乙醇产量。结果表明,当pH为2.0、不含Na_2SO_4时,OD_(600 nm)值(4.8)和乙醇产量... 该研究以东方伊萨酵母(Issatchenkia orientalis)FJ-J-3为研究对象,利用分光光度计法和气相色谱(GC)法测定其在不同pH和不同Na_2SO_4含量胁迫下的生长状况和乙醇产量。结果表明,当pH为2.0、不含Na_2SO_4时,OD_(600 nm)值(4.8)和乙醇产量(1.3%vol)最高;当pH为4.0、Na_2SO_4含量为2%时,OD_(600 nm)值(26.5)和乙醇产量(3.0%vol)最高;当pH为6.0、Na_2SO_4含量为6%时,OD_(600 nm)值(27.5)和乙醇产量(2.9%vol)最高;当pH为8.0、Na_2SO_4含量为2%时,OD_(600 nm)值(20.9)和乙醇产量(2.3%vol)最高。菌株FJ-J-3在pH=4.0和pH=6.0培养条件下具有较好的盐耐受性;在pH=2.0和pH=8.0的条件下,菌株FJ-J-3对盐的耐受性减弱。 展开更多
关键词 东方伊萨酵母Fj-j-3 环境胁迫 乙醇产量 生物量
下载PDF
J酸的合成及其在直接染料、活性染料中的应用
16
作者 孙桂春 《染料与染色》 CAS 2012年第3期21-25,共5页
本文论述了J酸的合成方法,探讨了J酸制备过程中副产物γ酸的生成过程及其控制方法。根据《世界染料品种—2005》公开的染料品种结构,对于J酸及其衍生物在直接染料和活性染料中的使用情况做了分析。
关键词 j 副产物 直接染料 活性染料
下载PDF
J酸清洁生产新工艺的研究 被引量:2
17
作者 陈之基 孙孝然 +3 位作者 贾丽云 叶平 吴希文 王连生 《中国环境科学》 EI CAS CSSCI CSCD 北大核心 2001年第5期427-431,共5页
借助高压液相色谱研究了J酸清洁生产新工艺,优化了J酸制备的反应条件,按照新工艺,产品的干品含量(偶合值)高于95%,而杂质异构体γ酸含量低于0.5%,J酸对吐氏酸的总收率达76%,减少了废水的排放.
关键词 j 清洁生产 磺化 碱熔 高压液相色谱 工艺研究
下载PDF
Migrant Workers Age-Group Productivity Gap Is Key to Verifying Lewis Turning Point in Chin* 被引量:2
18
《China Economist》 2012年第2期90-100,共11页
This paper uses age-related productivity gaps to analyze the Lewis turning point in China. The age-related productivity gap implies that under same wage rate, older and less productive rural laborers working in cities... This paper uses age-related productivity gaps to analyze the Lewis turning point in China. The age-related productivity gap implies that under same wage rate, older and less productive rural laborers working in cities will earn less than the reservation wage. Thus, they may elect instead to return to the countryside. Therefore, this paper argues that while the supply of younger, high-productivity migrant workers fails demand and Lewis turning point emerges, there still exists a high volume of lower-productivity rural surplus labor. 展开更多
关键词 Lewis turning point productIVITY age difference migrant workersjEL: j61 j64 O15
下载PDF
Progress toward the Synthesis of Pochonin J
19
作者 Sydney N. Jackson Rongson Pongdee 《International Journal of Organic Chemistry》 2019年第2期96-105,共10页
The construction of the C(1) - C(5) fragment of the resorcylic acid lactone pochonin J is described. The synthesis is marked by the installation of the cis-1,3-diol moiety in a highly stereoselective manner using Evan... The construction of the C(1) - C(5) fragment of the resorcylic acid lactone pochonin J is described. The synthesis is marked by the installation of the cis-1,3-diol moiety in a highly stereoselective manner using Evans’ intra-molecular base-catalyzed oxyconjugate addition of a hemiacetal-derived nucleophile. The synthetic route presented affords an efficient pathway to the preparation of this critical architectural feature that should facilitate the development of this secondary metabolite as a potential drug candidate. 展开更多
关键词 NATURAL products Pochonin j Resorcylic ACID LACTONES
下载PDF
几类图的L(j,k)-标号数 被引量:3
20
作者 吴琼 《高师理科学刊》 2018年第8期1-3,共3页
一些计算机无线网络的代码分配问题可以抽象为强乘积图和轮图的L(j,k)-标号问题(j≤k).针对强乘积图和轮图的L(j,k)-标号问题展开研究,确定了路与路,路与圈以及圈与圈之间的强乘积图的L(j,k)-标号数(这里j≤k≤2 j)和轮图的L(j,k)-标号... 一些计算机无线网络的代码分配问题可以抽象为强乘积图和轮图的L(j,k)-标号问题(j≤k).针对强乘积图和轮图的L(j,k)-标号问题展开研究,确定了路与路,路与圈以及圈与圈之间的强乘积图的L(j,k)-标号数(这里j≤k≤2 j)和轮图的L(j,k)-标号数(这里j≤k≤2 j或k≥3j). 展开更多
关键词 轮图 强乘积图 代码分配问题 L(j k)-标号
下载PDF
上一页 1 2 4 下一页 到第
使用帮助 返回顶部