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排序方式: 共有1639条查询结果,搜索用时 15 毫秒
31.
Kamal A Tamboli JR Ramaiah MJ Adil SF Koteswara Rao G Viswanath A Mallareddy A Pushpavalli SN Pal-Bhadra M 《ChemMedChem》2012,7(8):1453-1464
A library of new anthranilamide-pyrazolo[1,5-a]pyrimidine conjugates were designed, synthesized, and evaluated for their anticancer activity in cervical cancer cells such as HeLa and SiHa that possess low levels of p53. All 24 conjugates showed antiproliferative activity, while some of them exhibit significant cytotoxicity. In assays related to cell-cycle distribution, these conjugates induced G(2) /M arrest in HeLa cells and G(1) cell-cycle arrest in SiHa cells. Immunocytochemistry assays revealed that these compounds cause nuclear translocation of p53, thereby indicating the activation of p53. In cervical cancer cells, the p53 protein is degraded by E6 oncoprotein. Immunoblot and RT-PCR analyses proved the presence of mitochondria-mediated apoptosis with involvement p53 target genes such as BAX, Bcl2, and p21 (CDKI). Moreover, these compounds increased the phosphorylated forms of p53 and provide signals for apoptosis induction. Interestingly, one of the conjugates, (2-phenyl-7-(3,4,5-trimethoxyphenyl)pyrazolo[1,5-a]pyrimidin-5-yl)(4-(2-(thiophen-2-ylmethylamino)benzoyl)piperazin-1-yl)methanone, is the most promising candidate in this series and has the potential to be taken up for further detailed studies. 相似文献
32.
Roger Mueller Rainer Jossen Sotiris E. Pratsinis Mark Watson M. Kamal Akhtar 《Journal of the American Ceramic Society》2004,87(2):197-202
Synthesis of zirconia nanoparticles by flame spray pyrolysis (FSP) at high production rates is investigated. Product powder is collected continuously in a baghouse filter unit that is cleaned periodically by air-pressure shocks. Nitrogen adsorption (BET), X-ray diffractometry (XRD), transmission electron microscopy (TEM), and thermogravimetric analysis (TGA) are used to characterize the product powder. The effect of powder production rate (up to 600 g/h), dispersion gas flow rate, and precursor concentration on product particle size, crystallinity, morphology, and purity is investigated. The primary particle size of zirconia is controlled from 6 to 35 nm, while the crystal structure consists of mostly tetragonal phase (80–95 wt%), with the balance monoclinic phase at all process conditions. The tetragonal crystal size is close to the primary particle size, which indicates weak agglomeration of single crystals. 相似文献
33.
Viscosity estimation of triacylglycerols and of some vegetable oils, based on their triacylglycerol composition 总被引:1,自引:0,他引:1
M. Noor Azian A. A. Mustafa Kamal F. Panau W. K. Ten 《Journal of the American Oil Chemists' Society》2001,78(10):1001-1005
The experimentally determined kinematic viscosities of simple triacylglycerols [trilaurin, trimyristin (MMM), tripalmitin (PPP), tristearin (SSS), triolein (OOO), and trilinolein (LiLiLi) were correlated to a modified Andrade-type equation. The constants for the modified equation were derived for each simple triacylglycerol. The method was also used to estimate the viscosity of mixed triacylglycerols [1,2-dimyristoyl-3-palmitoyl (MMP), 1,2-dioleoyl-3-palmitoyl (OOP), 1,2-dimyristoyl-3-oleoyl (MMO), and 1,2-dipalmitoyl-3-oleoyl (PPO)], binary triacylglycerol mixtures (PPO/OOP, PPP/SSS, and OOO/SSS of different portions), and three types of vegetable oils [refined, bleached, and deodorized palm oil; cocoa butter; and canola oil] by applying modified Kay’s rule utilizing the simple triacylglycerol constants derived earlier. In all cases, the estimated values for liquid viscosity were compared with experimental values determined in this work and with previous work from the literature. When applied to vegetable oils, the method requires knowledge of their triacylglycerol composition. Despite its simplicity, the method gives a reasonable estimate. The method may be used to predict the viscosity of different blends of vegetable oils, and the accuracy is expected to increase when more experimental data on simple triacylglycerols become available. 相似文献
34.
35.
The hydrolytic depolymerization of molten PET in excess water was studied using a 2 L stirred pressure reactor at temperatures of 250, 265, and 280°C. Rate constants for hydrolysis are calculated from the initial rate data. At initial water: PET charge ratios (w/w) exceeding 5.1, essentially complete depolymerization to monomer is possible at 265°C. At lower water: PET initial charges, an equilibrium is established. The equilibrium constants are calculated for 2 g water/g PET at three temperatures. A kinetic model is proposed to describe the hydrolysis reaction. The model is shown to fit experimental data and to yield good predictions for the equilibrium concentration of carboxyl groups. Carboxyl-group concentrations are measured using an end-group analysis technique. Potentiometric titrations are carried out in one of two solvent systems, dimethylphenol:chloroform or dimethylsulfoxide, depending on the extent of hydrolysis. © 1993 John Wiley & Sons, Inc. 相似文献
36.
Maryam Safarbeiranvnd Hakimeh Amanipoor Sedigheh Battaleb-Looie Kamal Ghanemi Behrouz Ebrahimi 《Water Resources Management》2018,32(11):3611-3628
In this research, based on the qualitative data of 40 wells, variations of water quality parameters of the Central Plain Aquifer were evaluated using kriging and IDW (Inverse Distance Weighting) methods. Owing to the normal distribution of the studied parameters (except Na+, SO42?, and TH: total hardness), ordinary kriging was used for modeling. The analysis of the data trends indicated that all the variables were influenced by in two general trends, i.e., NW–SE and NE–SW. In fact, these trends were a result of the effect of the structural conditions on aquifer properties such as transmissivity and flow direction. Variogram analysis (based on C0 near zero and C0/σ2 ratio between 0.0–0.5) showed that the Na+, TDS (total dissolved solids), Ca2+, and TH variables have a good spatial structure and the BOD (biochemical oxygen demand), COD (chemical oxygen demand), NO3?, and EC variables have poor spatial structure. The BOD, COD, NO3?, and EC (electrical conductivity) variables have the smallest range and isotropic distribution. On the other hand, the Ca2+, Mg2+, Na+, SO42?, Cl?, HCO3?, pH, TDS, TH and Alk (alkalinity) parameters are characterized by anisotropic distributions. The Na+, TDS, Ca2+, and TH variables have the largest range. The results showed that both the IDW and kriging methods have close estimates to one another. The pH variable decreases toward the outlet whereas the EC and TDS variables increase along the direction of water flow and toward the outlet. The distributions of the BOD and COD variables do not perfectly match with the aggregation of industrial activities in the central part as well as the agricultural activities in the southeastern and central parts of the aquifer. The distributions of the Ca2+, Mg2+, and Alk variables completely follow the geology condition and regional spread of carbonate formations. The Na+ concentration increases from the center toward the outlet. The concentration of the Cl? variable is the highest in the central part of the plain due to the concentration of agricultural and industrial activities. The distribution of the SO42? variable is influenced by a natural factor (lithology), especially in the southeastern parts and the outlet as well as artificial factors (agricultural and industrial activities) in the central and southeastern parts of the aquifer. The NO3? variable, which is directly influenced by agricultural and livestock-farming activities, has its maximum concentration in the southeastern areas. 相似文献
37.
Shakila Ansari;Noushin Mohammadifard;Parisa Hajihashemi;Fahimeh Haghighatdoost;Ehsan Zarepur;Shirin Mahmoudi;Fatemeh Nouri;Fereydoon Nouhi;Tooba Kazemi;Nahid Salehi;Kamal Solati;Samad Ghaffari;Mahboobeh Gholipour;Mostafa Dehghani;Mostafa Cheraghi;Habib Heybar;Hassan Alikhasi;Nizal Sarrafzadegan; 《Food Science & Nutrition》2024,12(5):3322-3335
Dairy products may affect hypertension (HTN) risk. The aim of this study was to examine the association between fermented and nonfermented dairy foods and HTN in a sample of premature coronary artery disease (PCAD) subjects. This cross-sectional study was performed on 1854 PCAD patients. A 110-item food frequency questionnaire was used to assess dietary intakes. HTN was considered if systolic blood pressure was 140 mmHg and higher and/or diastolic blood pressure was 90 mmHg and higher. The odds ratio of HTN across the quartiles of different types of dairy products was evaluated by binary logistic regression. The mean (SD) of dairy products consumption was 339.8 (223.5) g/day, of which 285.4 g/day was fermented dairy products. In the crude model, participants in the fourth quartile of fermented dairy products had lesser risk of HTN compared to the bottom quartile (OR = 0.70, 95% CI: 0.52, 0.96; p for trend = .058). However, after considering the possible confounders, the significance disappeared. Subjects in the top quartile of high-fat fermented dairy products had 34% lower risk for HTN compared to the bottom quartile (95% CI: 0.49, 0.88; p for trend < .001). Adjustment for potential risk factors weakened the association but remained significant (OR = 0.73, 95% CI: 0.53, 1.01; p for trend = .001). Nonsignificant relation was detected between low-fat fermented, low-fat nonfermented, and high-fat nonfermented dairy products and HTN. Moderate consumption of high-fat fermented dairy products, in a population with low consumption of dairy foods, might relate to reduced likelihood of HTN. 相似文献
38.
Sahar Mahmoud Kamal;Walaa Mahmoud Elsherif;Antonio Valero;Alshimaa Mohammed Faried; 《Journal of Food Safety》2024,44(6):e70003
Tallaga cheese is the most popular type of white soft cheese in Egypt. Cronobacter sakazakii is an opportunistic foodborne pathogen that poses a threat to the health of almost every age group, with a particular emphasis on neonates and infants. Essential oils (EOs), such as olive oil and thyme oil, exhibit a broad-spectrum antibacterial effect. However, few studies have investigated the antibacterial activity of these EOs and their formulated nanoemulsions (NEs)—olive oil nano-emulsions (ONE) and thyme oil nano-emulsions (TNE)—on C. sakazakii in cheese to date. The purpose of this study was to investigate the inhibitory effects of these EOs and their NEs on the development of C. sakazakii during the processing and storage of Tallaga cheese. Additionally, the organoleptic properties of the resulting cheese were evaluated. Herein, ONE and TNE were prepared and characterized using a zetasizer and transmission electron microscopy (TEM). Furthermore, the minimum inhibitory concentrations (MICs) of EOs and NEs were determined using well diffusion assay. Fresh buffalo's milk for the elaboration of Tallaga cheese was inoculated with C. sakazakii at a concentration of 6 log CFU/mL, along with the addition of MICs of either EOs or NEs. The obtained results showed that the MICs were 15 mg/mL (v/v) for either olive oil, thyme oil, ONE and TNE with diameter inhibition zones of 10.3 ± 0.5, 13.3 ± 1.7, 12.3 ± 0.5, and 16 ± 0.8 mm, respectively. In addition, NEs exhibited high antibacterial activities against C. sakazakii in comparison to pure EOs. Particularly, the strongest antibacterial effect toward C. sakazakii was reported with TNE during manufacturing and storage of Tallaga cheese. Overall, these results suggest that thyme and its NEs have the potential to prevent bacterial contamination by C. sakazakii in the dairy industry. 相似文献
39.
Ankit Sachan Shyam Kamal Sorin Olaru Devender Singh Xiaogang Xiong 《国际强度与非线性控制杂志
》2020,30(6):2443-2460
》2020,30(6):2443-2460
This article presents a hands‐off control design for discrete‐time nonlinear system with a special type of nonlinear sector termed as “discrete‐time sector.” The design method to define the boundary of a discrete‐time sector is done with control‐Lyapunov function. The generalization of nonlinear system is viewed in the perspective of a comparison function. By means of a proposed sector, a switching control is designed such that no control action is experienced inside the sector thus, saving unnecessary control efforts. However, to study the robustness for discrete‐time system, a hands‐off control is modified to ensure the monotonic decrease in the energy of the system. Finally, the proposed approach is verified with the simulation results. 相似文献
40.
This paper presents a new hybrid approach for multiaxial fatigue life estimation, based on continuum damage mechanics theory and a genetic algorithm with critical plane model formulation. The hybrid model employs a genetic algorithm based setup for calibration with standard proportional and non‐proportional profiles to predict fatigue life for complex loading profiles. The model is evaluated using experimental fatigue life data for SS304 steel. Calibration using simplified profiles is in agreement with the requirement for cost‐effective experimental fatigue life testing. In‐phase and out‐of‐phase loads are used for calibration, and fatigue life is predicted for more complicated profiles. The results show good agreement between the estimated and experimental fatigue life, and calibration through simple loading histories to predict fatigue life for complex histories appears to be an effective solution using the proposed model. A brief comparison is presented with fatigue life estimation performance of the proposed model with models available in commercial codes. Proposed model found to be more consistent in fatigue life prediction against various loading conditions. 相似文献