oalib

Publish in OALib Journal

ISSN: 2333-9721

APC: Only $99

Submit

Any time

2019 ( 146 )

2018 ( 3771 )

2017 ( 3799 )

2016 ( 4137 )

Custom range...

Search Results: 1 - 10 of 183191 matches for " 陈维 "
All listed articles are free for downloading (OA Articles)
Page 1 /183191
Display every page Item
一种新的超导体系——Ba-R-Cu-O体系(R=Sm,Eu,Nd,Eu+Y)

科学通报 , 1987,
Abstract: Bednorz和Müller报道了在Ba-La-Ca-O体系中T_c约为30~35K的超导电性。Chu和赵忠贤等分别宣布了在Ba-Y-Cu-O系中T_c约为90K的超导电性。这些结果表明在其它稀土氧化物体系中,存在着高T_c超导的可能性。我们研究了Ba-R-Cu-O体系(R=Sm、Eu、Nd、Eu+Y),在这些体系中,观察到了超导现象。
2005-2012年我国信息共享空间(ic)研究述评
 
图书馆工作与研究 , 2014,
Abstract: ?本文利用文献综述方法,从定量和定性两个角度,对2005年至2012年我国信息共享空间研究的期刊论文进行分析,总结了我国信息共享空间研究的不足之处,并对今后的研究提出了相应的建议。
黄化变异对英红九号红茶香气的影响

- , 2018, DOI: 10.13982/j.mfst.1673-9078.2018.10.031
Abstract: 英红九号的黄化变异植株嫩梢存在叶绿体发育缺陷,叶片光合作用与代谢积累的改变或会影响茶叶品质。为明确黄化变异对红茶香气的影响,本文分别以黄化变异和叶色正常英红九号为原料加工试验和对照红碎茶,比较样品间感官香气与化合物的变化。感官审评结果表明,黄化红碎茶的香气浓度整体弱于对照,尤其在甜度与鲜度上。利用顶空固相微萃取和气相色谱-串联质谱法,从两组样品中鉴别出56种香气化合物。依据出现频次和单因素方差分析筛选出49种差异成分,随后进行化学计量分析与基于衍生途径的分类。结果表明,利用49种化合物作为主成分能清晰区分两组样品;10种化合物有组成差异,其中黄化样品的香气种类较少;39种化合物有含量差异,其中28种化合物在黄化样品中显著下降,11种上升。差异香气主要涉及脂肪酸、类胡萝卜素氧化和萜类代谢相关的衍生途径。
The chlorina Yinghong9 which occur in yellow young leaves during growing stage is a result of abnormal chloroplast development. The changes of photosynthesis and metabolite accumulation in chlorina Yinghong9 might potentially affect the quality of its processed tea. To reveal the possible tea aroma changes caused by chlorina, cut-tear-curl (CTC) black tea prepared from the chlorina and normal Yinghong9, marked as HY and CK (control) respectively, were selected to valuate sensory aroma quality and volatile organic compounds (VOCs). The result of sensory evaluation indicated that an overall aroma intensity of HY black tea (especially in attributes of sweetness and freshness) decreases in comparison to the CK. A total of 56 VOCs were identified by headspace-solid phase mircoextraction (HS-SPME) coupled with gas chromatography-triple quadrupole mass spectrometry (GC/MS/MS) among the samples. Forty-nine differential VOCs were obtained between the sample groups according to the frequency of occurrence as well as univariate analysis. These VOCs were applied to chemometrics analyses and pathway-based classification subsequently. Clear separation was achieved among HY and CK samples in score plot of principle component analysis (PCA). Ten differential VOCs demonstrated composition variation between sample groups where HY black teas presented VOC varieties in lesser amount. Thirty-nine differential VOCs showed content variation between sample groups, and 28 of them decreased in HY black teas while the other 11 ones increased. The differential VOCs were mainly related to the tea aroma derivation pathways of fatty acid and carotenoids oxidation as well as the terpenoid biosynthesis.
基于化学计量学分析堆青时间对白茶香气的影响

- , 2018, DOI: 10.13982/j.mfst.1673-9078.2018.05.035
Abstract: 堆青是一种有利于茶叶香气转化的手段,本文研究了堆青时间对白茶香气的影响,并分析了感官香气与化合物变化间的联系。感官审评结果表明,堆青使白茶甜香增强而鲜度下降。通过顶空固相微萃取和气相色谱-串联质谱联仪从样品中表征出55种化合物,它们的组成受堆青影响甚微,但含量变化显著。基于化学计量学方法筛选并分析37种差异化合物;主成分分析和层次聚类分析均可区分不同堆青处理的样品,其中堆青前后样品间差异明显。苯乙醇、苯甲醛和苯乙醛等随堆青的总体上升,以及β-环柠檬醛、反-2-辛烯醛和α-紫罗兰酮在堆青后含量的普遍增加,可能是引起甜香增强的原因。而正己醇、反,反-2,4-己二烯醛和辛醛在堆青后含量的普遍减少,则可能与鲜度下降相关。32 h的堆青较有利于白茶香气的发展。化学计量学方法的引入使得样品间差异信息的获取更有效率。
Pile-up is a tea manufacture process,which is beneficial to the transformation of tea aroma.. In this study, the effect of pile-up processing duration on the white tea aroma was investigated, and the relationship between sensory aroma and the changes of volatile organic compounds (VOCs) along different durations was analyzed. The sensory evaluation results indicated that pile-up treatment could improve sweetness of white tea, but decreased freshness. A total of 55 VOCs were characterized through headspace-solid phase micro-extraction (HS-SPME) coupled with gas chromatography-triple quadrupole mass spectrometry (GC/MS/MS). The VOCs profiles showed that pile-up had little effect on the composition changes, but the content changed significantly. Chemometric approaches were applied to select and analyze the 37 differential VOCs patternsin white tea. The results showed that all samples of different pile-up treatments were distinguished based on the principle component analysis and hierarchical cluster analysis, of which the difference between samples was obvious before and after pile-up processing. The content of 2-phenylethanol, benzaldehyde, phenylacetaldehyde increased after pile-up treatment, as well as the content of β-cyclocitral, (E)-2-octenal and α-ionone widely increased in post-pile-up samples, which might be the cause of stronger sweetness flavor. However, the content of 1-hexanol, (E,E)-2,4-hexadienal and octanal in post-pile-up samples decreased widely, which might be related to the reduction of freshness. The 32h pile-up was considered as the optimum duration for processing white tea. The introduction of chemometric approaches in VOCs analysis facilitated in revealing the variations and exploring the biochemical patterns among samples.
心理契约违背对反生产行为的影响作用研究——以心理资本为调节变量
Study on the Effect of Psychological Contract Violation on Counter-Productive Behavior——With Psychological Capital as a Moderator
 [PDF]

, 王琛, 黄丽
Advances in Psychology (AP) , 2012, DOI: 10.12677/ap.2012.21004
Abstract: 企业员工反生产行为及其后果的严重性引起了国内外学者的重视,本研究通过对167名国企员工的有效调查样本进行分析发现:1) 员工的心理契约违背感受对其反生产行为的发生程度有显著的正向预测作用;2) 员工的心理资本对其反生产行为的发生程度有显著的负向预测作用;3) 员工的心理资本对其心理契约违背感受和反生产行为之间的关系起到显著的负向调节作用。
Counter-productive behavior and its serious consequences of employees have attracted the atten- tion of domestic and foreign scholars. This study analyzed 167 valid samples from state-owned companies and the results showed that: 1) Psychological contract violation of employees had a significant positive im- pact on the occurrence of counter-productive behavior; 2) Psychological capital of employees predicted nega- tively the occurrence of counter-productive behavior; 3) Psychological capital of employees played a signi- ficant negative moderating effect on the relationship between psychological contract violation and counter- productive behavior.
NF-КBP65和BCL-2蛋白在多形性腺瘤中的表达
The Expression of NF-КBP65 and BCL-2 Protein in Pleomorphic Adenoma
 [PDF]

昌晖,
Hans Journal of Biomedicine (HJBM) , 2016, DOI: 10.12677/HJBM.2016.61001
Abstract:
目的:检测NF-КBP65与BCL-2蛋白在多形性腺瘤及瘤旁正常涎腺组织中的表达情况,探讨NF-КBP65与BCL-2蛋白在多形性腺瘤的表达意义。方法:采用免疫组织化学S-P法检测20例涎腺多形性腺瘤组织石蜡标本中NF-КBP65与BCL-2蛋白表达水平,以瘤旁正常涎腺组织作为对照,进行组内及组间比较。结果:多形性腺瘤和瘤旁正常涎腺组织中NF-КBP65表达的阳性率分别为55%和10.0%,差异有统计学意义(P<0.05);BCL-2表达的阳性率分别为35%和10.0%,差异有统计学意义(P<0.05)。结论: NF-КBP65 和BCL-2的协同作用可能对多形性腺瘤的发生、发展起重要作用。
Objective: To detect the expression and discuss the expression meaning of NF-КBP65 and BCL-2 protein in pleomorphic adenoma. Methods: The expression of NF-КBP65 and BCL-2 protein in pa-raffin embedded specimens of pleomorphic adenoma and adjacent normal salivary gland tissue of 20 cases was detected using immunohistochemical S-P method. Results: The positive rates of NF-КBP65 expression in pleomorphic adenoma and adjacent normal salivary gland tissue were? 55% and 10%, and the positive rates of BCL-2 expression were 35% and 10% respectively. The differences of NF-КBP65 and BCL-2 expression in pleomorphic adenoma and tumor adjacent normal salivary gland tissue were statistically significant (P < 0.05). Conclusion: NF-КBP65 and BCL-2 may play an important role in pleomorphic adenoma occurrence and development.
Strengthening Awareness of Public Relations to Build Good Image of Sci-tech Journal
强化公关意识 重视科技期刊形象建设


中国科技期刊研究 , 2003,
Abstract: 为提高科技期刊的竞争力,保持持续发展,期刊社应强化公关意识,重视期刊形象建设。
第二届全国半导体物理学术会议简讯

半导体学报 , 1980,
Abstract: <正> 第二届全国半导体物理学术会议于1979年11月8日至14日在安徽省合肥市召开.出席这次会议的有领导机关、研究单位、高等院校、情报出版、工厂等74个单位的135名代表.11月8 日上午,由中国物理学会常务理事、中国科学院半导体所所长黄昆主持开幕式.安徽省委第一书记万里,
炸药爆轰波的渡形控制及应用

力学与实践 , 1984,
Abstract: 控制炸药爆轰波的波形和提高炸药利用率已是许多学者研究的课题,也是工程上提出的要求,炸药爆轰波具有“光学”的特性,在传播过程中碰到障碍物也会被反射与衍射.一些研究者应用这个规律性,控制并得到各种类型波形,如精确控制爆轰波的形状使它聚焦,它就能引爆原子弹.柱面收缩波能够得到很高的压力与温度,用它合成新材料,在常规武器弹药
金属玻璃与爆炸加工

力学与实践 , 1984,
Abstract: 金属玻璃,亦称非晶态合金,它是近十几年来兴起的一种新材料,与一般合金相比具有强度高、韧性好、超耐腐蚀及高导磁等特性.经常采用有 Fe_(8c)·P_(18)·C_7·Fe_2·Ni_8·P_(13)·C_7及贵金属的 Pd_(30)·Si_(2c)等.六十年代金属玻璃仅仅是实验室的珍品,七十年代国外采用新工艺方法制成非晶态合金带及细丝做为商品出售,当时在世界上引起很大的反响.世界各国对非晶态合金的研究极为重视,1974年美国把非晶态合金的研究列为三大重点课题之一.
Page 1 /183191
Display every page Item


Home
Copyright © 2008-2017 Open Access Library. All rights reserved.