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81.
Heavy metal fluoride (HMF) glass optical fibres were spliced by fusing the two ends of fibres using a DC arc. An average optical loss of 0.08 dB per splice and strengths of up to 600 MPa were achieved for fusion splices using an inert gas purge during splicing. Estimates are made to determine the feasibility of achieving a splice loss of 0.005 dB for single-mode (HMF) fibres.<> 相似文献
82.
Chappell MA Laird DA Thompson ML Li H Teppen BJ Aggarwal V Johnston CT Boyd SA 《Environmental science & technology》2005,39(9):3150-3156
Smectites, clay minerals commonly found in soils and sediments, vary widely in their ability to adsorb organic chemicals. Recent research has demonstrated the importance of surface charge density and properties of exchangeable cations in controlling the affinity of smectites for organic molecules. In this study, we induced hysteresis in the crystalline swelling of smectites to test the hypothesis that the extent of crystalline swelling (or interlayer hydration status) has a large influence on the ability of smectites to adsorb atrazine from aqueous systems. Air-dried K-saturated Panther Creek (PC) smectite swelled less (d(001) = 1.38 nm) than never-dried K-PC (d(001) = 1.7 nm) when rehydrated in 20 mM KCl. Correspondingly, the air-dried-rehydrated K-PC had an order of magnitude greater affinity for atrazine relative to the never-dried K-PC. Both air-dried-rehydrated and never-dried Ca-PC expanded to approximately 2.0 nm in 10 mM CaCl2 and both samples had similar affinities for atrazine that were slightly lower than that of never-dried K-PC. The importance of interlayer hydration status in controlling sorption affinity was confirmed by molecular modeling, which revealed much greater interaction between interlayer water molecules and atrazine in a three-layer hydrate relative to a one-layer hydrate. The entropy change on moving atrazine from a fully hydrated state in the bulk solution to a partially hydrated state in the smectite interlayers is believed to be a major factor influencing sorption affinity. In an application test, choice of background solution (20 mM KCl versus 10 mM CaCl2) and air-drying treatments significantly affected atrazine sorption affinities for three-smectitic soils; however, the trends were not consistent with those observed for the reference smectite. Further, extending the initial rehydration time from 24 to 240 h (prior to adding atrazine) significantly decreased the soil's sorption affinity for atrazine. We conclude that interlayer hydration status has a large influence on the affinity of smectites for atrazine and that air-drying treatments have the potential to modify the sorption affinity of smectitic soils for organic molecules such as atrazine. 相似文献
83.
Wood samples and veneers of Hevea brasiliensis (Rubber wood) and Acacia auriculaeformis treated with aqueous solutions of chromium trioxide, ferric chloride and ferric nitrate were studied for water repellency and their reaction with wood constituents. FTIR spectra obtained from wood surface treated with chromium trioxide indicate the formation of a water insoluble complex between chromium trioxide and aromatic ring of lignin, whereas no reaction takes place with ferric salts. Treatment of wood by chromium trioxide was found to be effective in imparting water repellency in wood. 相似文献
84.
Santosh Kumar Dash Pradip Lingfa Supriya B. Chavan 《Energy Sources, Part A: Recovery, Utilization, and Environmental Effects》2018,40(24):2923-2932
From the inception of commercialization of biodiesel, feedstock scarcity is a major issue to be pondered upon in developing countries. In this study, an attempt has been made to use an abundantly available underutilized high oil content (67% of Nahar seed kernel) feedstock derived biodiesel in a compression ignition engine. The experimental investigation on diesel engine reveals slightly reduced brake thermal efficiency and excellent exhaust emissions up to 40% blending of Nahar biodiesel with conventional diesel fuel. At full load, compared to diesel fuel, the BTE dropped by 1.64% and 1.83%, whereas the BSFC increased by 5.07% and 6.76% for B30 and B40 blends, respectively. The tested emission parameters such as CO, HC, NOx, and smoke were decreased by 12.66%, 17.99%, 8.31%, and 10.61% for B30 and 4.87%, 12.76%, 7.98%, and 11.78% for B40, respectively, compared to diesel fuel.
Abbreviation: BD: Biodiesel; DF: Diesel fuel 相似文献
85.
Pooja Sarotra Gayatri Sharma Shevali Kansal Anjana Kumari Negi Ritu Aggarwal Rajat Sandhir Navneet Agnihotri 《Lipids》2010,45(9):785-798
n-3 Polyunsaturated fatty acids (PUFA) have a chemopreventive effect while n-6 PUFA promote carcinogenesis. The effect of
these essential fatty acids may be related to oxidative stress. Therefore, the study was designed to evaluate the effect of
different ratios of fish oil (FO) and corn oil (CO) in the prevention of colon cancer. Male Wistar rats were divided into
control, dimethylhydrazine dihydrochloride (DMH) treated, FO + CO (1:1) and FO + CO (2.5:1). All the groups, except the control
received a weekly injection of DMH for 4 weeks. The animals were sacrificed either 48 h later (initiation phase) or kept for
16 weeks (post initiation phase). DMH treatment in the initiation phase animals showed mild to moderate inflammation, decreased
ROS and TrxR activity, increased antioxidants, apoptosis and ACF multiplicity. The post initiation study showed severe inflammation
with hyperplasia, increased ACF multiplicity and ROS levels, a decrease in antioxidants and apoptosis. The FO + CO (1:1) treated
animals showed severe inflammation, a decrease in ROS, an increase in antioxidants and apoptosis in the initiation phase.
FO + CO (1:1) in the post initiation phase and FO + CO (2.5:1) in the initiation showed mild inflammation, increased ROS,
apoptosis and decreased antioxidants. There was a decrease in ACF multiplicity and ROS levels, increased antioxidants and
apoptosis in the post initiation phase study. The present study suggests that FO has a dose- and time-dependent chemopreventive
effect in colon cancer mediated through oxidative stress and apoptosis. 相似文献
86.
Agrawal Yash Kumar Manoranjan Ananthakrishnan Supriya Kumarapuram Gopalakrishnan 《Water Resources Management》2022,36(3):1025-1042
Water Resources Management - The present study investigates and evaluate the scope and potential of modern computing tools and techniques such as ensembled machine learning methods in estimating... 相似文献
87.
Telecommunication Systems - Energy saving in User Equipment (UE) is one of the important issues for limited sources of power in the device. It is critical for the UE to maximize its energy... 相似文献
88.
89.
O. Auciello A. M. Dhote R. Ramesh B. T. Liu S. Aggarwal A. H. Mueller 《Integrated ferroelectrics》2013,141(1):295-306
We review our studies of film growth and interface processes performed using complementary in situ and ex situ characterization techniques that provide valuable information critical to the development of materials integration strategies for the fabrication of electroceramic film-based devices. Specifically, we review our work performed using in situ time-of-flight ion scattering and recoil spectroscopy (TOF-ISARS) / X-ray photoemission spectroscopy (XPS) / spectroscopic ellipsometry (SE), in conjunction with ex situ TEM and other techniques to study film growth and interface processes critical to the fabrication of non-volatile ferroelectric memories (NVFRAMs), dynamic random access memories (DRAMs), and high frequency devices based on high-K thin films. TOF-ISARS involves three distinct but closely related experimental methods, namely: ion scattering spectroscopy, direct recoil spectroscopy and mass spectroscopy of recoiled ions, which provide monolayer-specific information on film growth and surface segregation processes. Spectroscopic Ellipsometry enables investigation of buried interfaces. XPS provides valuable information on the chemistry of surface and interfaces. Specifically, we discuss: a) studies of oxidation of Ti-Al layers and synthesis and properties of La 0.5 Sr 0.5 CoO 9 /Ti-Al heterostructured layers for integration of PZT capacitors with Si substrates, and b) studies of BaSr x Ti 1 m x O 3 layer integration with Si substrates relevant to DRAMs, high frequency devices and high-K gate oxides for integrated circuits. This review shows the power of combined in situ / ex situ analytical techniques to provide valuable information for material integration strategies for electroceramic thin film-based devices. 相似文献
90.
Dipesh Aggarwal Latha Sabikhi Heena Lamba Neha Chaudhary Rajeev Kapila 《International Journal of Food Science & Technology》2017,52(1):118-126
A fibre‐enriched, reduced‐calorie biscuit [formulated biscuit (FB)] was evaluated for its antidiabetic and antilipidaemic potential in streptozotocin‐induced diabetes in Wistar rats against control biscuit (CB) having high calorie and low fibre content. Animals were allocated into five groups: a control group fed with synthetic diet, two diabetes‐induced groups (CBD and FBD) and two nondiabetic groups (CBND and FBND). CBD and CBND were fed with synthetic diet + CB while FBD and FBND were fed with synthetic diet + FB. After 6 weeks of feeding, the change in weight of nondiabetic group fed with FB (+16.20%) was nonsignificantly lower compared to control (+33.01%) and CB‐fed (+34.55%) group. Nonsignificant loss in body weight was observed among diabetic group fed with FB (?11.76%) or CB (?36.88%). Feeding of FB led to a significant decrease in fasting and postprandial blood glucose levels, total cholesterol, triglycerides, LDL‐C, VLDL‐C and atherosclerotic index and increase the HDL‐C. Histological examination showed that feeding of FB was able to partially recover the destroyed β‐cell in STZ‐induced diabetic rats. 相似文献