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991.
The objective of this study was to develop a novel floating in situ gel system for sustained drug delivery of acetohydroxamic acid (FIGA) for eradication of Helicobacter pylori (H. pylori). The FIGA was prepared by dissolving the different concentration of gellan in deionized water at 80 degrees C. Different concentration of drug and calcium carbonate as floating agents were dispersed with stirring. In vitro results revealed that in situ gelling formulation forms rigid gels instantaneously and floated for longed period time of time in SGF pH 1.2. The formulation parameters, such as concentration of polymer, concentration of calcium carbonate, and concentration of drug, affected the in vitro drug release characteristic significantly. Absence of drug-polymer interaction was confirmed by differential scanning calorimetry analysis. The in vivo H. pylori clearance efficacy of prepared FIGA in reference to acetohydroxamic acid suspension following repeated oral administration to H. pylori-infected Mongolian gerbils was examined by microbial culture method. FIGA showed a significant anti-H. pylori effect in the in vivo gerbil model. It was noted that the required amount of acetohydroxamic acid for eradication of H. pylori was very less in FIGA than in the corresponding acetohydroxamic acid suspension. From the above results, it was concluded that the floating in situ gelling system has feasibility for forming rigid gels in the stomach and eradicated H. pylori from the gastrointestinal tract more effectively than acetohydroxamic acid suspension because of the prolonged gastrointestinal residence time of the formulation. 相似文献
992.
The success of the company lies in understanding the customer preferences and tastes and anticipating the changes required in existing or new products being offered. This study uses a heuristic approach to formulate the problem of product development using a combination of analytical hierarchy process (AHP) with quality function deployment (QFD) to evaluate the most satisfying design for customer. A case study for selection of a bike has been presented here to illustrate the proposed approach.
The contributions of the article are (a) structuring of the decision problem for assessment of impact of decisions after identification of customer attributes and preferences; (b) assessing strategies to synthesize qualitative and quantitative factors in decision-making, keeping checks on consistency; (c) using the additive synthesis of priorities to accommodate a variety of interactions and transform multidimensional measurements to unidimensional ratio scale; and (d) assessing the impact of the engineering characteristics weights on the priority of the criteria and overall project (v) Validation of the model using case study. 相似文献
The contributions of the article are (a) structuring of the decision problem for assessment of impact of decisions after identification of customer attributes and preferences; (b) assessing strategies to synthesize qualitative and quantitative factors in decision-making, keeping checks on consistency; (c) using the additive synthesis of priorities to accommodate a variety of interactions and transform multidimensional measurements to unidimensional ratio scale; and (d) assessing the impact of the engineering characteristics weights on the priority of the criteria and overall project (v) Validation of the model using case study. 相似文献
993.
Sutar PB Mishra RK Pal K Banthia AK 《Journal of materials science. Materials in medicine》2008,19(6):2247-2253
In the present study an attempt was made to graft polyacrylamide on pectin. The grafted polymer was characterized by FTIR
spectroscopy, differential scanning calorimetry and X-ray diffraction. Rheological property of pectin solution was compared
with the product solution. The grafted polymer was cross-linked with varying amount of glutaraldehyde. The swelling properties
of the cross-linked product were also studied. The salicylic acid, an antipyretic drug, was incorporated in the cross-linked
gel as a model drug and the drug release studies were done in a modified Franz’s diffusion cell. The effect of cross-linking
density on the release property of salicylic acid was studied through the cross-linked product. The product showed better
film forming property and gelling property than pectin. The comparative rheological properties of pectin and grafted copolymer
indicated change in the property of the product. FTIR studies indicated incorporation of amide group. Differential scanning
calorimetry and XRD suggested formation of a new polymer. Swelling study indicated pH dependent swelling of the cross-linked
hydrogel. Salicylic acid release indicated pH dependent release from the hydrogel. 相似文献
994.
John Komlos Bhoopesh Mishra Antonio Lanzirotti Satish C. B. Myneni Peter R. Jaffé 《Canadian Metallurgical Quarterly》2008,134(2):78-86
The biological reduction of uranium from soluble U(VI) to insoluble U(IV) has shown potential to prevent uranium migration in groundwater. To gain insight into the extent of uranium reduction that can occur during biostimulation and to what degree U(IV) reoxidation will occur under field relevant conditions after biostimulation is terminated, X-ray absorption near edge structure (XANES) spectroscopy was used to monitor: (1) uranium speciation in situ in a flowing column while active reduction was occurring; and (2) in situ postbiostimulation uranium stability and speciation when exposed to incoming oxic water. Results show that after 70 days of bioreduction in a high (30?mM) bicarbonate solution, the majority (>90%) of the uranium in the column was immobilized as U(IV). After acetate addition was terminated and oxic water entered the column, in situ real-time XANES analysis showed that U(IV) reoxidation to U(VI) (and subsequent remobilization) occurred rapidly (on the order of minutes) within the reach of the oxygen front and the spatial and temporal XANES spectra captured during reoxidation allowed for real-time uranium reoxidation rates to be calculated. 相似文献
995.
William Casey Rhiannon Weaver Jose Andre Morales Evan Wright Bud Mishra 《Mobile Networks and Applications》2016,21(1):161-174
We present a game theoretic framework that models strategic interactions among humans and things that are assumed to be interconnected by a social-technological network, as in an internet of humans and things (IOHT). Often a pair of agents in the network interacts in order for an informed sender-agent to signal an uninformed receiver-agent to take an action that benefits each of the players; the benefits to the pair of agents are modeled by two separate utility functions, both depending on the sender’s private information, the signal exchanged, and the receiver’s revealed (and also possibly unrevealed) action. In general, the two agents’ utilities may not be aligned and may encourage deceptive behavior. For example, a sender, aware of his/her own private “state of ignorance”, may seek useful information from a receiver who owns powerful computational resources to search a large corpus of webpages; the sender does so by sending a signal to the receiver in the form of a keyword. Obvious examples of deceptiveness here range from attempts to hide one’s intentions to auctioning the keywords on an ad exchange through real-time bidding. A rather troublesome situation occurs when deceptions are employed to breach the security of the system, thus making the entire social-technological network unreliable. Earlier, we proposed a signaling-game-theoretic framework to alleviate this problem. This paper further enhances that framework by reconfiguring signals to possess more complex structures (epistatic signals to represent attack and defense options over a given set of vulnerabilities). We explore two augmentations to the original evolutionary signaling game by first enhancing mutation bias toward strategies performing well in previous populations and second allowing the parameters of the utility functions to depend on population preferences giving rise to a minority game with epistatic signaling. The resulting game systems are empirically studied through extensive computer simulation. 相似文献
996.
Effect of thermal pretreatment on recovery of nickel and cobalt from Sukinda lateritic nickel ore using microorganisms 总被引:1,自引:0,他引:1
Smaranika Mohapatra Chandan Sengupta Bansi Dhar Nayak Lala Bihari Sukla Barada Kanta Mishra 《Korean Journal of Chemical Engineering》2008,25(5):1070-1075
Experimental investigation made previously on microbiological leaching of nickel and cobalt from the laterite nickel ore of
Sukinda Valley reveals that the recovery was not very much promising under any favorable conditions. Therefore, in order to
improve the efficiency for bioleaching, the homogenized lateritic ore in palletized form is thermally pretreated by roasting
at different temperatures. The parameters studied for the bioleaching experiments were the four types of pretreated ore which
were roasted at different temperatures, i.e., 300 °C, 400 °C, 600 °C and 800 °C, in shake flask by using a mixed mesophilic
acidophilic bacterial consortium consisting predominantly of the Acidithiobacillus ferrooxidans strain. It was observed that the pretreated ore at 600 °C with 10% (w/v) pulp density showed maximum recovery of nickel and
cobalt, i.e., 59.18% (4.556 ppm) and 65.09% (0.546 ppm), using 10% (v/v) (2.5 × 108 cells/ml) consortium concentration at 1.5 pH, 30 °C, and 150 rpm after an incubation period of 31 days. 相似文献
997.
Study of quaternary aquifers in Ganga Plain, India: focus on groundwater salinity, fluoride and fluorosis 总被引:1,自引:0,他引:1
In marginal and central alluvial plains (Ganga Plain) of India, the inland salinity is continuously increasing, canal network and arid to semi-arid climatic conditions that led to excessive evapotranspiration concentrates the salt in soil and thereby escalating the groundwater salinity. In Mat Tahsil, Mathura district (Ganga Plain) study on shallow and deep aquifer salinity and fluoride was carried out in August 2001 and 2004. Groundwater salinity in some parts is more then 4000 microOmega(-1)/cm. This region is severely affected by endemic fluorosis due to consumption of fluoride-contaminated water. Analysis of F(-), Na(+), K(+), Cl(-) and HCO(3)(-) was carried out at 30 sites of dugwells and borewells. Result shows that there is a variation and continuous escalation in the groundwater salinity and fluoride concentration in deep and shallow aquifers on the basis of analysis. Classification of salinity levels was carried out in 2001 and 2004. The deep aquifers (borewells) are found more saline as compare to the shallow aquifers (dugwells) while F(-), Na(+), K(+), Cl(-) and HCO(3)(-) shows high concentration in shallow aquifers. The fluoride concentration in the groundwater of these villages showed values from 0.1 to 2.5mg/l, severe enough to cause dental and skeletal fluorosis among the inhabitants, especially children of these villages. One of the major effects of inland salinity in this region is from saline groundwater, which is reaching the land surface and causing soil salinisations and water logging in the NE and SE parts of Mat block. 相似文献
998.
In the present study, catalytic thermal treatment (thermolysis) was investigated for the reduction of COD and color of the desizing wastewater under moderate temperature and atmospheric pressure conditions using various catalysts. The experimental runs were performed in a glass reactor equipped with a vertical condenser. The homogeneous copper sulfate catalyst was found to be the most active in comparison to other catalysts under similar operating conditions. A removal of about 71.6% chemical oxygen demand (COD) and 87.2% color of desizing wastewater was obtained with a catalyst concentration of 4 kg/m(3) at pH 4. The initial pH value of the wastewater showed a pronounced effect on the precipitation process. During the thermolysis, copper gets leached to the aqueous phase, the residue obtained after the treatment is rich in copper and it can be blended with organic manure for use in agricultural fields. The thermogravimetric analysis showed that the thermal oxidation of the solid residue obtained after thermolysis gets oxidized at a higher temperature range than that of the residue obtained from the desizing wastewater. The results lead to the conclusion that thermochemical precipitation is a very fast (instantaneous) process and would need a very small reactor vessel in comparison to other processes. 相似文献
999.
Jiye Wang Jianqing Su Rajiv S. Mishra Ray Xu John A. Baumann 《Journal of Materials Engineering and Performance》2014,23(8):3027-3033
A preliminary study of deformation behavior of friction stir welded (FSW) Ti-6Al-4V was performed using two different tools with cylindrical and stepped spiral pin design for the welding process. The nugget regions experienced temperature above β transus and the matrix transformed to fine acicular α during cooling of the nugget. By using stepped spiral pin design, a local region with much refined grain structure and significant tool debris particles were observed. Room temperature tensile test showed increased strength and decreased ductility in the material from this region. Fractographic analysis revealed that tool debris particles served as void nucleation sites. Tensile tests of FSW material were carried out at 625 °C in the strain rates of 3 × 10?4 and 1 × 10?3 s?1. The strength was higher as compared to the as-received material. Microstructural evolution during tensile test was also investigated. Results showed that dynamic globularization occurred during the high temperature tensile test. 相似文献
1000.
A new method of determining forming limit diagram for sheet materials by gas blow forming 总被引:1,自引:0,他引:1
G. Mitukiewicz K. Anantheshwara G. Zhou R.K. Mishra M.K. Jain 《Journal of Materials Processing Technology》2014,214(12):2960-2970
A new methodology is proposed to obtain forming limit diagrams (FLDs) of sheet materials using gas blow forming process at elevated temperatures. Tension–tension side of the forming FLD is achieved by using circular as well as elliptical dies of different aspect ratios. To achieve tension–compression side of FLD un-bonded bi-layer specimen with slots are utilized. The widths between the slots are varied to achieve different strain paths. A correlation is established between the hemispherical punch-based tests and GBF tests of samples with slots to achieve different strain paths. FLDs for automotive AZ31 magnesium sheet at 300 °C and 400 °C in two different orientations are determined. Increase in forming limits of AZ31 with increase in temperature is observed. 相似文献