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981.
982.
Medical practitioners are unduly stressed, leading to ill health, loss of work efficiency, sometimes affecting decision-making capability. The present study was conducted with the aim to quantify the psychosocial factors that affect the medical practitioners working in Indian hospitals. This study constructed and validated Re-Modified Work-Style Short Form Questionnaire, an eight-item instrument based on work style of 108 medical practitioners comprising Indian physicians and surgeons. The re-modified tool had acceptable validity and internal consistency, which the modified one did not. Explorative factor analysis identified and labelled three factors: ‘Working through pain’, ‘Deadlines/pressure’ and ‘Self-imposed workload’. The findings of the study reveal that the mean total work style score exceeded the standardised limits ≥16, which suggests that the work style of medical practitioners working in Indian hospitals are at risk which may precipitate psychosocial stress. Factor weights was derived through Analytic Hierarchy Process to prioritise the relative importance of three potential work-style factors. The study may help to increase the preventive strategies to proactively reduce the effect of risk factors for the precipitation of stress, successfully leading to its attenuation. 相似文献
983.
Under water-rich conditions, small amphiphilic and hydrophobic drug molecules self-assemble into supramolecular nanostructures. Thus, substantial modifications in their interaction with cellular structures and the ability to reach intracellular targets could happen. Additionally, drug aggregates could be more toxic than the non-aggregated counterparts, or vice versa. Moreover, since self-aggregation reduces the number of effective “monomeric” molecules that interact with the target, the drug potency could be underestimated. In other cases, the activity could be ascribed to the non-aggregated molecule while it stems from its aggregates. Thus, drug self-assembly could mislead from drug throughput screening assays to advanced preclinical and clinical trials. Finally, aggregates could serve as crystallization nuclei. The impact that this phenomenon has on the biological performance of active compounds, the inconsistent and often controversial nature of the published data and the need for recommendations/guidelines as preamble of more harmonized research protocols to characterize drug self-aggregation were main motivations for this review. First, the key molecular and environmental parameters governing drug self-aggregation, the main drug families for which this phenomenon and the methods used for its characterization are described. Then, promising nanotechnology platforms investigated to prevent/control it towards a more efficient drug development process are briefly discussed. 相似文献
984.
Shunting effect is the loss of electrical current via the secondary circuit provided due to existence of previous nugget in a series of welding spots. This phenomenon is important for products containing intermittent spots. In this study, a theoretical model is developed for shunting effect in resistance spot welding for aluminum alloy 2219. Welding distance together with welding current and time is included in the model to analyze the shunting effect on final nugget quality. Thermal and electrical interactions are considered in the model as well as geometrical aspects of the process. Temperature dependence of material properties, integration through the whole volume of the nugget and heat-affected zone, and assuming a simple cooling mechanism are the most important modifications designated in the proposed theoretical model. Predicted results of nugget diameter are compatible with experimental and finite element analysis results. 相似文献
985.
A prediction method for color changes based on the time–temperature superposition principle (TTSP) was developed for acetaminophen solution. Color changes of acetaminophen solution are caused by the degradation of acetaminophen, such as hydrolysis and oxidation. In principle, the TTSP can be applied to only thermal aging. Therefore, the impact of oxidation on the color changes of acetaminophen solution was verified. The results of our experiment suggested that the oxidation products enhanced the color changes in acetaminophen solution. Next, the color changes of acetaminophen solution samples of the same head space volume after accelerated aging at various temperatures were investigated using the Commission Internationale de l’Eclairage (CIE) LAB color space (a*, b*, L* and ΔE*ab), following which the TTSP was adopted to kinetic analysis of the color changes. The apparent activation energies using the time–temperature shift factor of a*, b*, L* and ΔE*ab were calculated as 72.4, 69.2, 72.3 and 70.9 (kJ/mol), respectively, which are similar to the values for acetaminophen hydrolysis reported in the literature. The predicted values of a*, b*, L* and ΔE*ab at 40?°C were obtained by calculation using Arrhenius plots. A comparison between the experimental and predicted values for each color parameter revealed sufficiently high R2 values (>0.98), suggesting the high reliability of the prediction. The kinetic analysis using TTSP was successfully applied to predicting the color changes under the controlled oxygen amount at any temperature and for any length of time. 相似文献
986.
目的研究新字库开发过程中的形态调整规则及设计方法,提升字库开发的质量。方法基于中国传统书法体与印刷体的美学概念,结合现代信息传播条件下新字库的应用需求,归纳字库开发中的形态调整规则,并剖析在中英文字库产业化研发中的创意设计方法。结论在中英文新字库开发的产业化及规模化过程中,以字体的灰度均衡、重心调节、缩放调整、结构均衡为核心的形态调整规则,是提升产品质量的保证;同时,采用多种设计方法进行整合与推演,能够提升新字库研发的创意效率。 相似文献
987.
988.
989.
990.
目的发展工业设计是当前我国增强制造业核心竞争力、优化产业结构、转变经济发展方式的手段,也是实施创新驱动发展战略的关键。掌握本土工业设计机构的发展状况,并研究其模式,有助于引导工业设计产业在日益激烈的国际竞争和新一轮工业革命的形势下探索有效的发展途径。方法以长三角地区宁波市的工业设计机构为研究样本,通过实地调研,结合访谈、问卷等方法。结论可以初步发现,在我国制造业发达地区,部分本土工业设计机构正在尝试突破传统的设计服务模式,结合自身资源和不同情况开拓更丰富的业务模式。这种现象显示了未来工业设计机构的发展方向,对本土工业设计持续发展具有启发意义。 相似文献