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101.
某型雷达电路板测试适配器需要对二十多种电路板进行功能测试,被测电路板信号时序复杂,接口定义不统一,给适配器设计带来困难。本文采用通用适配器设计方案成功的解决了问题,实践证明,该适配器设计灵活,大大简化多电路板检测适配器的设计难度,具有一定的工程借鉴价值。  相似文献   
102.
Lubricious thin films are used in plastic medical syringes in order to reduce the frictional forces between the syringe barrel and the rubber plunger. Polydimethylsiloxane (PDMS) liquid films are the current accepted technology for reducing the friction forces in plastic medical syringes. However, major issues with these PDMS films exist, including interactions of the film with the stored injectable drugs and variations in the frictional response as the syringes are aged over time. A new silicon based, lubricious octamethylcyclotetrasiloxane (L-OMCTS) thin film solid lubricant has been developed as a replacement for PDMS that provides acceptable and stable frictional responses without interacting with injectable drugs. A novel test method has been developed that can be used to successfully characterise the sliding frictional response of the L-OMCTS thin films at the syringe barrel and plunger interface. This test method will be used to provide future insight into how the frictional response of the L-OMCTS thin films is affected by various system parameters. This paper will mainly discuss the design of this new test method and provide some preliminary frictional response data.  相似文献   
103.
气井稳定携液之我见   总被引:1,自引:0,他引:1  
业内对于临界携液流量的认识一直都存在着分歧。以Turner、李闽为代表的液滴携液理论观点认为"当气体流速达到一定数值后,液相分散成小液滴被携带走";而以李颖川等为代表的气液两相管流实验模拟者则认为"在气井生产过程中雾状流很难出现,气井生产基本上是以段塞流为主,液滴模型无法解释气井实际排液情况"。为了还原低压低产气井实际生产状态,基于弗劳德相似准数,以流速相似原理模拟低压、低产井实际生产情况,并开展了相应的实验研究。结果表明:①低压、低产气井实际上存在"上雾+下段塞"混合流动状态;②上部雾状流携液满足液滴模型计算结果,当气相流速高于临界携液流速则上部可连续带液,否则会导致积液段液量缓慢增加;③下部表现为段塞流,当气相流速高于1.95 m/s,则表现为连续流动,气井基本无积液,当气相流速低于0.195 m/s,则表现为难以流动,气井不产液,面临水淹。实验所得结果与气井实际生产情况相当吻合,可以为气井有效开采提供技术支撑。  相似文献   
104.
深水探井测试对于深海油气田的勘探发现和开发方案的制订起着至关重要的作用。为此,针对琼东南盆地陵水凹陷深水测试面临的海床温度低、管柱压力大,以及地层水或凝析水具有生成天然气水合物(以下简称水合物)堵塞测试管柱等技术难题,在分析总结南海北部珠江口盆地多口深水探井与国外合作测试作业成功经验的基础上,研究形成了该区测试期水合物形成区域预测及水合物防治方法;建立了基于临界测试流量设计测试工作制度;结合地质录井、MDT测井等资料.建立了可视化数值试井模型并对压力恢复时间进行合理设计;通过对深水测试管柱结构的优化,提出了深水测试一开一关的测试程序,从而达到多开多关测试程序的功能;通过对地面测试流程的模块化方案设计,增强了深水测试的安全性和高效性。实践结果表明:测试期间水合物和地层出砂得到了有效防治.测试管柱及模块化地面流程经受住了高产气流的考验,获得了完整的测试资料,节省了测试时间,达到了准确评价储层的目的,并基本形成了我国的深水油气井测试技术。  相似文献   
105.
In this paper, we propose a novel methodology to define and estimate a surrogate measure. By imposing a hypothetical disturbance to the leading vehicle, the following vehicle’s action is represented as a probabilistic causal model. After that, a tree is built to describe the eight possible conflict types under the model. The surrogate measure, named Aggregated Crash Index (ACI), is thus proposed to measure the crash risk. This index reflects the accommodability of freeway traffic state to a traffic disturbance. We further apply this measure to evaluate the crash risks in a freeway section of Pacific Motorway, Australia. The results show that the proposed indicator outperforms the three traditional crash surrogate measures (i.e., Time to Collision, Proportion of Stopping Distance, and Crash Potential Index) in representing rear-end crash risks. The applications of this measure are also discussed.  相似文献   
106.
为了使干硬性混凝土试件制作更具有代表性,从制作过程中的密度控制、振动层数、振动时间与混凝土28天的标养强度的相关关系中,找出适合于干硬性混凝土试件的制作方法.  相似文献   
107.
总结介绍圆钢微裂纹、刮伤缺陷的检验与判定,以及根据镦锻检验结果判定缺陷原因的方法。  相似文献   
108.
This paper presents about conceptual designs of Advanced Recycling Reactor (ARR) focusing on enhancement in transuranics (TRU) burning and americium (Am) transmutation. The design has been conducted in the context of the Global Nuclear Energy Partnership (GNEP) seeking to close nuclear fuel cycle in ways that reduce proliferation risks, reduce the nuclear waste in the US and further improve global energy security. This study strives to enhance the TRU burning and the Am transmutation, assuming the development of related technologies in this study, while the ARR based on mature technologies was designed in the previous study. It has followed that the provided TRU burning core is designed to burn TRU at 28 kg/TWthh, by adding moderator pins of B4C (Enriched B-11) and the Am transmutation core will be able to transmute Am at 34 kg/TWthh, by locating Am blanket of AmN around the TRU burning core. It indicates that these concepts improve TRU burning by 40-50% than the previous core and can transmute Am effectively, keeping the void reactivity acceptable.  相似文献   
109.
采用硅钢片磁性能测试系统,分析了测试环境温度(10~30℃)、试样质量(642~667 g)和剪切应力(剪切1~5次)对国内外不同牌号0.27~0.50 mm取向和无取向冷轧硅钢片磁性能的影响.结果表明,随环境温度升高,冷轧硅钢片的铁损和磁感降低;随试样质量增加,铁损增加,磁感降低;随剪切次数增加铁损递增,磁感递减.文中归纳出磁性能测量的适合条件和注意事项.  相似文献   
110.
Previous studies have demonstrated that patients with borderline personality disorder (BPD) tend to misattribute malevolence to benign social stimuli, including facial expressions. Yet, facial emotion recognition studies examining those with BPD have yielded mixed results, with some studies showing impaired accuracy and others demonstrating enhanced accuracy in the recognition of emotions or mental states. The current study examined the ability to decode mental states from photographs of just the eye region of faces in a nonclinical sample of young adults who exhibited BPD traits (high BPD) compared with those who did not (low BPD). Group differences in mental state decoding ability depended on the valence of the stimuli. The high-BPD group performed better for negative stimuli compared with the low-BPD group, but did not perform significantly different from the low-BPD group for stimuli of neutral or positive valence. The high-BPD group also demonstrated a response bias for attributing negative mental states to facial stimuli. In addition, findings suggested that the group difference in accuracy for negative stimuli could not be explained by response bias, because the group difference in response bias for negative stimuli did not reach significance. These findings suggest that BPD traits may be associated with enhanced ability to detect negative emotions and a bias for attributing negative emotions to nonnegative social stimuli. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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