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121.
This paper describes methodology for direct and indirect detections of a specific oligonucleotide for Epstein-Barr virus (EBV) using electrochemical techniques. The sequence of oligonucleotide probe (EBV1) revealed a high sequence identity (100%) with the EBV genome. For the development of the genosensor, EBV1 was grafted to the platform sensitized with poly(4-aminothiophenol). After that, the hybridization reaction was carried out with the complementary target (EBV2) on the modified electrode surface using ethidium bromide as DNA intercalator. The oxidation peak currents of ethidium bromide increased linearly with the values of the concentration of the complementary sequences in the range from 3.78 to 756 μmol·L−1. In nonstringent experimental conditions, this genosensor can detect 17.32 nmol·L−1 (three independent experiments) of oligonucleotide target, discriminating between complementary and non-complementary oligonucleotides, as well as differentiating one-base mismatch, as required for detection of genetic diseases caused by point mutations. The biosensor also displayed high specificity to the EBV target with elimination of interference from mix (alanine, glucose, uric acid, ascorbic acid, bovine serum albumin (BSA), glutamate and glycine) and good stability (120 days). In addition, it was possible to observe differences between hybridized and non-hybridized surfaces through atomic force microscopy.  相似文献   
122.
The likelihood of cyber-attacks against information systems and related production control systems has increased. In order to lower the risk of cyber-attacks, OS makers release timely security updates. However, the amount of time that is available for applying patches is limited on production control systems and the possibility of side effects is a concern. Therefore, we focused on the patch application cycle and the period of pretest, and proposed optimal OS measures for production control systems. We presented the method for quantifying the risk of cyber-attacks on production control systems due to security patches not being applied and for expressing the risk as a monetary amount. This method was also proposed for deriving the patch application cycle, the number of applications, and the optimum test duration. We concluded that this method help to understand the patch management and related security measure and to protect production control systems from cyber-attacks.  相似文献   
123.
This study is devoted to recognizing the breathing resistances of wearing respirators from respiratory and surface electromyography (sEMG) signals. Ten subjects were required to sit for 5 min and walk for 5 min while wearing two different models of N95 filtering facepiece respirators (FFRs) and without a respirator. We recorded the sEMG signals from the respiratory muscles of the subjects, and the respiratory amplitude is also collected. Subsequently, fifteen features of the sEMG time domain and respiratory amplitude were extracted and used as input vectors to a recognition model based on artificial neural networks (ANNs). Finally, the experimental results show that these artificial neural networks are effective for recognizing different airway resistances of wearing respirators from sEMG and respiratory signals. The results also indicate that abdominal and scalene are the primary respiratory muscles affected by using N95 FFRs.Relevance to industryRespirator manufactures and administrations can readily employ this paper's findings for recognizing the breathing resistances of wearing respirators from respiratory and surface electromyography (sEMG) signals based on artificial neural networks automatically. Observations of the present study are in support of testing only the two primary muscles (abdominal and scalene) to simplify the evaluation of the effects of the breathing resistances of wearing respirators on respiratory muscles.  相似文献   
124.
彭静  宋静  栾家杰 《金属学报》2021,26(9):1073-1079
当前新型冠状病毒肺炎(corona virus disease 2019, COVID-19)全球蔓延,全球累计确诊超过16 750万例。新型冠状病毒传播具有高传染性,人体感染后具有呼吸道症状、发热、严重呼吸综合征、器官衰竭,甚至死亡。对于COVID-19目前没有特异性治疗方法,大部分治疗方案采用的是对症支持治疗,但是预后差。间充质干细胞(mesenchymal stem cells, MSCs)不仅能够修复损伤的肺组织,还具有调控免疫、抗炎等作用,具有良好的临床应用前景。本文将对MSCs应用于新冠病毒肺炎治疗做一综述,以供同行参考。  相似文献   
125.
本文为了阻止Android手机恶意软件病毒的危害,分析了入侵病毒的类型,提出了一个基于Android平台的安全检测软件的设计方案,并实现了该方案。该软件基于Android的体系机构,结合Android体系自身的特点,实现了查杀病毒、检测支付环境、监听电话短信、检测流量等功能,保障了用户的安全。经过真机和模拟机测试,该软件能够有效查杀病毒、检测到潜在的病毒危害并及时采取措施,达到了设计目的。  相似文献   
126.
邢娜 《电子测试》2015,(2):134-135,114
随着网络信息时代的到来,计算机技术已经应用到了社会生活的方方面面,在各个领域因为计算机互联网技术而获得方便、高效、进步的同时,计算机网络的安全问题也成为了当前计算机领域的一个重要问题。计算机病毒,成为了威胁计算机网络安全的一个重要隐患,我们在享受计算机所给我们带来的便利同时,也要面对计算机病毒所带给我们的困难和挑战;由于计算机病毒具有寄生性、传染性、潜伏性、隐蔽性等特征,使得计算机病毒无法完全根治,又由于计算机病毒也随会随着计算机的发展而不断更新发展,这使得计算机病毒安全防御工作难题不断,本文便试图讨论计算机病毒的安全防御策略。  相似文献   
127.
胶体金免疫电镜技术检测番茄环纹斑点病毒   总被引:1,自引:0,他引:1  
本实验利用胶体金免疫电镜技术检测番茄环纹斑点病毒( tomato zonate spot virus, TZSV),分别以TZSV的N 蛋白多克隆抗体及TZSV的Gn蛋白多克隆抗体为一抗,然后以胶体金标记羊抗兔IgG?gold(10 nm)为二抗对病毒进行胶体金标记,电镜观察用TZSV Gn蛋白抗体标记的胶体金颗粒能很好地结合到病毒粒体上。结果表明该方法可以实现对TZSV更为准确可靠地检测。  相似文献   
128.
Hepatitis C virus (HCV) chronically affects millions of individuals worldwide. The HCV nonstructural protein 5A (NS5A) plays a critical role in the viral assembly pathway. Domain 3 (D3) of NS5A is an unstructured polypeptide responsible for the interaction with the core particle assembly structure. Casein kinase 2 (CK2) phosphorylates NS5A‐D3 at multiple sites that have mostly been predicted and only observed indirectly. In order to identify the CK2‐dependent phosphorylation sites, we monitored the reaction between NS5A‐D3 and CK2 in vitro by time‐resolved NMR. We unambiguously identified four serine residues as substrates of CK2. The apparent rate constant for each site was determined from the reaction curves. Ser408 was quickly phosphorylated, whereas the three other serine residues reacted more slowly. These results provide a starting point from which to elucidate the role of phosphorylation in the mechanisms of viral assembly—and in the modulation of the viral activity—at the molecular level.  相似文献   
129.
130.
Dendrimers are novel three dimensional, hyperbranched globular nanopolymeric architectures. Attractive features like nanoscopic size, narrow polydispersity index, excellent control over molecular structure, availability of multiple functional groups at the periphery and cavities in the interior distinguish them amongst the available polymers. Applications of dendrimers in a large variety of fields have been explored. Drug delivery scientists are especially enthusiastic about possible utility of dendrimers as drug delivery tool. Terminal functionalities provide a platform for conjugation of the drug and targeting moieties. In addition, these peripheral functional groups can be employed to tailor-make the properties of dendrimers, enhancing their versatility. The present review highlights the contribution of dendrimers in the field of nanotechnology with intent to aid the researchers in exploring dendrimers in the field of drug delivery.  相似文献   
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