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1.
The optical and morphological properties of resveratrol were investigated. This nontoxic fluorescent natural material, emitting in the visible blue light, was used as an optical marker, enabling the enhancement of the image contrast coming from relief pictures marked on challenging surfaces. By applying appropriated imaging softwares, this marker was verified to be very useful in the latent fingerprint recognition deposited on different wood surface types, mainly those with high level of roughness, where conventional forensic materials do not allow effective fingerprint image visualization.  相似文献   
2.
Abstract

Goals in the public sector are complex and managers can face situations in which pursuing one legitimate goal necessitates performance trade-offs in other areas. This study tests how knowledge of legitimate performance trade-offs shapes the perception of red tape. Using a vignette experimental design and a sample of university students, between group t-tests and regression analyses suggest that, when evaluating increased rule burden, individuals that are provided with information about how objectively burdensome rules serve alternative values such as equity and effectiveness associate them with lower levels of red tape. A series of Monte Carlo simulations suggest that this effect is substantial.  相似文献   
3.
商品房买卖面积争议是商品房买卖合同纠纷的表现形式,对其进行分析和探讨,有利于商品房买卖面积争议处理更为科学合理并保证当事人权利救济途径更加顺畅。  相似文献   
4.
柔嫩艾美球虫杨凌株表面抗原SAG10基因的克隆与原核表达   总被引:2,自引:0,他引:2  
从柔嫩艾美球虫第二代裂殖子总RNA中扩增EtSAG10基因,与pGEM-T Easy载体连接后转化大肠杆菌(E.coli)DH5α,筛选阳性克隆,扩增不含N端信号肽的编码序列,分别插入表达载体pET-32a( )和pMAL-c2X,转化至E.coliRosetta,以IPTG诱导表达。结果表明,pET-32a( )-EtSAG10在E.coliRosetta中的表达产物约占菌体总蛋白的43%,融合蛋白分子质量约为47 ku,以包涵体形式存在;而pMAL-c2X-EtSAG10在E.coliRosetta中表达的重组蛋白为可溶性,表达产物约占菌体总蛋白的35%,融合蛋白分子质量约为69 ku。以表达的可溶性EtSAG10重组蛋白100μg/只肌肉注射免疫雏鸡,攻虫后以盲肠病变计分、盲肠卵囊数(OPG)、相对增重率和抗球虫指数(ACI)评价,免疫组相对盲肠卵囊产量为47.7%,抗球虫指数由86.79提高至152.13。提示,重组表达的EtSAG10可诱导雏鸡产生一定的抗球虫免疫保护。  相似文献   
5.
地上权制度是用益物权制度框架内的一项基本制度,经济和社会的发展使地上权具有了崭新的内容,在我国土地所有权归国家和农村集体经济组织所有的条件下具有广泛的适用范围,尤其是有助于解决城市用地、工业用地、居民住宅建设用地,以及在他人所有的土地上下铺设管道等公共设施而产生的权利义务关系,从而促进社会经济的发展。  相似文献   
6.
目的 通过三维重建测量上、下颌尖牙髓腔/牙体表面积比值(Pulp/Tooth area Ratio,PTR)来推断个体年龄,为临床年龄推断的应用提供科学依据.方法 收集口腔门诊患者年龄在16~65岁200例锥形束CT(Cone beam computed tomography,CBCT)影像资料,以4个尖牙为测量对象并...  相似文献   
7.
通过对200余种透明胶带紫外导数光谱分析,确定了最佳分析条件,验证了分析方法的重现性和稳定性。分析了不同胶带紫外导数光谱产生变化的原因,证明紫外导数光谱法是一种快速、简单、可靠、实用的鉴别透明胶带来源的方法。  相似文献   
8.
现场勘查中,技术人员对用粉末刷显的手印、灰尘加层手印拍照提取后,再用新型手印提取器提取效果更好。手印提取器使胶带与客体接触面积变小、压力均匀,从而避免在提取过程中产生气泡;同时,胶带具有粘性的一面与另一胶带紧密相粘,通过转动,能制成透明的手印检材,可直接通过印相放大、复印,或通过反差较大的衬底做背景进行比对鉴定。实践证明,运用手印提取器提取的手印具有高质量、手印特征反映好、保存时间长,而且在使用中方便简捷,提取速度快等优点。  相似文献   
9.
Virtual anthropology (VA) is based on applying anthropological methods currently used to analyse bones to 3D models of human remains. While great advances have been made in this endeavour in the past decade, several interrogations concerning how reliable these models are and what their proper use should be remain unanswered. In this research, a fundamental assumption of VA has been investigated: if the way we perceive and apply an anthropological method is truly similar when looking at bones macroscopically and through various 3D media. In order to answer, 10 skulls of known age and sex were scanned using a computed tomography (CT) scanner and a 3D surface scanner. Two observers separately applied a defined staging method to eight suture sites on these skulls, first looking at the bone macroscopically, then at the 3D surface scan, and finally on the CT scan. Two rounds of observation were carried out by each observer. Intra- and inter-observer error were evaluated, and two sample t-tests used to evaluate if the different types of medium used yielded significantly different observations. The results show a high degree of inter-observer error, and that data obtained from 3D surface scans differ from macroscopic observation (confidence level 95%, P ≤ 0.05). CT scans, in these settings, yielded results comparable to those obtained through macroscopic observations. These results offer many possibilities for future research, including indications on the kind of anthropological methods and anatomical landmarks that might be reliably transferable to the virtual environment. All current methods used in traditional anthropology should be tested, and if they prove unreliable, new techniques to analyse bones from virtual models should be developed.

Key points

  • Large discrepancies between observation on dry bones and computer-generated 3D models (surface scans or CT scans) could lead to the re-evaluation of the suitability of traditional anthropological methods for application on 3D models.
  • This preliminary study evaluates whether macroscopic, 3D surface scans, and CT scans viewings generate different observations.
  • The results indicate that the data are not always coherent across all three media of observation.
  • Explanations include the aspect given to the bone by the 3D software, differences between handling bones in real life versus on a computer, and level of expertise of the observers.
  相似文献   
10.
X-ray photoelectron spectroscopy (XPS) is a widely used technique to characterize the surface chemistry of materials. It plays a crucial role in accessing qualitative and quantitative information and in detecting the presence of chemical functional groups on the surface of any material. The forensic methods available to detect and identify elements and organic/inorganic compounds are often destructive, so evidence cannot be re-analyzed. However, XPS allows rapid analysis of samples without damaging them. Recently, an increasing number of forensic researchers have begun to study certain chemical information on fingermarks. In this study, the authors aimed to present the applicability and power of XPS imaging in fingermark analysis which can also provide specific information about the fingermark chemical composition. Herein, monochromated X-ray (Al Kα) spot size was fixed at 50 μm. XPS mapping resulted in the acquisition of spectra at each pixel, in an array of 41 × 30 pixels with a step size of 50 μm. Then, a simple discussion has been made about how the scanned surface spectrum and basic snapshot spectra are used to identify different components at a fingertip of a scanned surface area (~3 mm2). Hence, a fingermark pattern contaminated with caffeine, TiO2, and Pb/PbO deposited on the silicon wafer can be chemically mapped and visualized by XPS using principal component analysis (PCA). Thus, the present study showed the possible applicability of XPS for the identification of illicit drugs of abuse, gunshot residue, and skin care products on latent fingermark by mimicking a crime scene evidence.  相似文献   
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