全文获取类型
收费全文 | 188篇 |
免费 | 17篇 |
专业分类
各国政治 | 8篇 |
工人农民 | 4篇 |
世界政治 | 18篇 |
外交国际关系 | 31篇 |
法律 | 107篇 |
中国共产党 | 1篇 |
政治理论 | 36篇 |
出版年
2024年 | 2篇 |
2023年 | 7篇 |
2022年 | 5篇 |
2021年 | 7篇 |
2020年 | 10篇 |
2019年 | 15篇 |
2018年 | 9篇 |
2017年 | 16篇 |
2016年 | 15篇 |
2015年 | 10篇 |
2014年 | 3篇 |
2013年 | 37篇 |
2012年 | 2篇 |
2011年 | 8篇 |
2010年 | 6篇 |
2009年 | 4篇 |
2008年 | 5篇 |
2007年 | 2篇 |
2006年 | 4篇 |
2005年 | 6篇 |
2004年 | 5篇 |
2003年 | 1篇 |
2002年 | 3篇 |
2001年 | 2篇 |
1999年 | 1篇 |
1996年 | 1篇 |
1992年 | 2篇 |
1990年 | 1篇 |
1989年 | 1篇 |
1988年 | 1篇 |
1987年 | 1篇 |
1985年 | 2篇 |
1984年 | 2篇 |
1983年 | 1篇 |
1982年 | 1篇 |
1980年 | 2篇 |
1979年 | 1篇 |
1978年 | 2篇 |
1977年 | 1篇 |
1971年 | 1篇 |
排序方式: 共有205条查询结果,搜索用时 31 毫秒
191.
Ajit Kumar Ghose 《发展研究杂志》2013,49(1):27-49
This paper seeks to assess the significance of the celebrated inverse relationship between farm size and land‐productivity in the context of Indian agriculture. It is argued that the inverse relationship does not reflect a superiority of peasant production over wage‐labour‐based production as is often supposed. It exists independently of production relations and thus reflects only a static superiority of small‐scale over large‐scale production. An essential precondition for this superiority, however, is a backwardness of technology. With technological progress involving the introduction of chemical fertilizers, labour‐saving machinery and modern irrigation equipment, the inverse relationship is, therefore, likely to disappear 相似文献
192.
Anil Kumar Agarwal 《Policy Sciences》1987,20(1):19-30
Salivary gland sucrase activity fromSesamia inferens Wlk. was optimal at pH 5.8 and temperature 35°. It increased up to 1.5% final sucrose concentration, but higher concentrations
had no effect. A dialysed preparation showed a 37.5% reduction in the activity. It was accelerated by tryptophan and inhibited
by all other amino acids used.
Gut sucrase activity ofS. inferens was optimal at pH 6.2 and temperature 30°. It increased sharply up to 0.66% final sucrose concentration, and then gradually
up to 1.5% while further increase in the concentration had no effect. A dialysed preparation showed an 8% increase in activity.
Activity was not affected by serine; was accelerated by arginine, cystine, methionine, tryptophan and valine; and inhibited
by alanine, glutamine, glycine, hydroxyproline, leucine, phenylalanine, proline and tyrosine.
End-products increased with the incubation period and showed inhibitory effects. With the increase of enzyme concentration
the rate of sucrose hydrolysis also increased. K+ ions accelerated the activity of the dialysed preparation. It was also accelerated by Li++ ions up to their final concentration of 0.001 M, but inhibited when their final concentration increased (0.01 M and 0.025
M). TRIS also inhibited the activity.
Résumé Deux types d'extraits ont été étudiés séparément: la sucrase extraite des glandes salivaires et celle extraite de l'intestin moyen. L'activité optimale de la sucrase salivaire s'observe pour un pH 5,8 et une température de 35°; celle de la sucrase de l'intestin moyen pour un pH 6,2 et une température de 30°. Cependant les extraits dialysés, d' origine salivaire ou d'origine intestinale, ont une activité optimum pour un même pH (5,8). L'activité des deux sucrases s'accro?t proportionnellement à la durée de la période d'incubation. L'activité de la sucrase salivaire s'accro?t nettement, jusqu'à une concentration finale en sucrose de 1.5%, alors que pour la sucrase intestinale, 90% de l'activité maximale est réalisée pour une concentration finale en sucrose de 0.66%. Quand la concentration en sucrose atteint ou dépasse 1,5% il se forme alors un oligosaccharide dont la synthèse équilibre l'hydrolyse du sucrose, ce qui rend l'activité de la sucrase constante au-dessus d'une concentration finale en sucrose≥1,5%. Cette synthèse d'un oligosaccharide intervient quand on utilise une forte concentration de sucrase, ce qui entraine la production de glucose et fructose en grande quantité; avec une faible concentration de l'extrait on n'observe pas la synthèse d'oligosaccharide. Les ions K+ accélèrent l'activité des extraits dialysés, d'origine salivarie ou intestinale; les ions Li++ sont également favorables jusqu'à une concentration de 0,001 M, cette action devenant inhibitrice à partir de 0,005 ou 0.025 M; les ions TRIS, à 0,025 M ont également un effet inhibiteur. Certains acides aminés accélèrent l'activité de la sucrase salivaire ou intestinale, d'autres au contraire ont une action inhibitrice.相似文献
193.
Devi Prasad Dash Narayan Sethi Aruna Kumar Dash 《Journal of Public Affairs (14723891)》2021,21(1):e2163
This study examines the road accident rates from 29 Indian states and 6 Union Territories during 2006–2015. In this paper, we have employed several empirical techniques such as regression, generalized method of moments (GMM), and threshold regression models to examine how education and attitude of the drivers impact the road accident rates. In our empirical analysis, we demonstrate that lawless driving is found to be positive and statistically significant while incorporating both state and year effects. We also find some interesting result in the context of education and road accidents. We notice positive relationship between higher education and road accident rates across Indian states, which tells us highly educated people are more prone to road accidents as compared with less educated people. In the threshold analysis, the study discovers the positive relationship between road injury and accidents caused by people with higher education, in cases of considering road injury rate from drunken driving as the threshold variable. There appears to be a large number of behavioral issues emanating from higher education, which contributes significantly to the road accident rates in the Indian states. Hence, there is a need for policy intervention. 相似文献
194.
Objectives
To determine whether concentrations of crime documented in American cities such as Boston, Jacksonville, Minneapolis, Sacramento, and Seattle generalize to unique environments such as India.Methods
Two years of motor vehicle theft (MVT) and burglary incidents from two police stations in Jaipur, India are analyzed. The degree to which crime clusters is documented using nearest neighborhood hierarchical clustering (NNHC). These results are compared to several widely cited studies documenting concentrations in the United States.Results
The NNHC procedure identified five MVT hot spots, which accounted for just .09 % of the two station’s land, but over 13 % of these incidents, and four burglary hot spots, which accounted for less than 1 % of its land, but nearly 23 % of the incidents.Conclusions
Given the stark differences in the built environment and sociological makeup of Jaipur, a better understanding of the forces that cause crime to concentrate to a high degree needs to be discerned before implementing law-enforcement driven policies derived from the scholarship of American cities. Additional research should also seek to replicate not just the degree to which crime clusters in these unique environments, but also its stability over time and micro place variation.195.
If an eyewitness is exposed to a co-witness statement that incorrectly blames an innocent bystander for a crime, the eyewitness can be influenced by this statement and also blame the innocent bystander for the crime. This effect is known as blame conformity. In two studies, we examined whether or not this effect is influenced by the degree of confidence a co-witness expresses in her incorrect statement (Study 1) and an eyewitness’s own level of self-confidence (Study 2). Participant eyewitnesses first watched a crime video featuring a perpetrator and an innocent bystander, then read a co-witness statement about the crime that either correctly blamed the perpetrator, incorrectly blamed the innocent bystander, or blamed nobody (a control condition). They were then asked who committed the crime. In Study 1, participants who read an incorrect statement were at increased risk of engaging in blame conformity when the co-witness expressed a high level of confidence, compared to a low level of confidence, in the accuracy of her statement. In Study 2, participants who were lowest in self-confidence were at increased risk of engaging in blame conformity. The theoretical underpinnings of these effects are considered. 相似文献
196.
Maind SD Kumar SA Chattopadhyay N Gandhi Ch Sudersanan M 《Forensic science international》2006,159(1):32-42
Characterization and assessment of inks on sensitive documents for absolute/relative age determination is the challenging forensic problem in spite of practical difficulties. Tagging of ballpoint pen ink with suitable taggant(s) is a unique method to come out with definitive inferences on the detection of forgery in documents written with ballpoint pens. Selection of a proper taggant primarily depends on sensitivity of analytical determination and their absence in normal varieties of ink used for document writing. Rare-earth elements, from all technical considerations can be potential taggant(s) for inks. To ensure more compatibility with ink, 13 rare-earth thenoyltrifluoroacetonate chelates were prepared and characterized. The ballpoint pen inks were tagged with rare-earth thenoyltrifluoroacetonate chelates individually at about 1-100 ppm level depending on sensitivity of element under suitable optimized experimental conditions and instrumental sensitivity. Aliquots of such tagged ink having varying amounts of taggants were analyzed by ICP-MS and INAA. Satisfactory recoveries and a good linear relationship of intensity (signal) against concentrations/amounts were observed. Under the optimized experimental conditions, the detection limits were worked out. This study of tagging metal ions in combination with ICP-MS and NAA as an analytical tool can allow to draw various combination options based on different rare-earth chelates as suitable materials for tagging of ballpoint pen inks for absolute/relative age determination to aid in document related crime examination. The advantages and limitations of proposed analytical techniques are discussed. 相似文献
197.
198.
199.
200.
Dimple Bhatia MSc Chongtham Nimi MSc Sweety Sharma PhD Abhilash Kumar Das MSc Rajinder Singh PhD 《Journal of forensic sciences》2023,68(6):1982-1990
Sealing wax is used for maintaining the integrity and authenticity of a document or physical evidence. Any tampering with the seal calls into question the overall integrity and authenticity of the tangible evidence or document. In these circumstances, determining the authenticity of the sealing material (physical and chemical) becomes imperative. In this study, ATR-FTIR spectroscopy supported by chemometrics has been used to differentiate sealing wax samples belonging to 12 different brands available across India. All the samples were first melted, cooled, and then analyzed using ATR-FTIR spectroscopy in the mid-infrared region (4000–600 cm−1). The obtained spectra were first examined visually for the presence of different functional groups. Principal component analysis (PCA) and principal component analysis-linear discriminant analysis (PCA-LDA) were employed to analyze the sample clustering patterns and to categorize them into their respective groups, respectively. For classification, a PCA-LDA training model was applied, and it demonstrated 95.83% accuracy. The validation test resulted in an accuracy of 83.33%. PCA-LDA model offered 100% accurate prediction for samples on various substrates, including cloth, cardboard, and paper. A blind study was also performed using five unknown samples, which were accurately classified into their respective groups. PCA-LDA model will be helpful in providing investigative leads by linking a questioned sealing wax sample with its respective group. 相似文献