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91.
Water Resources Management - Accurate and reliable discharge estimation is considered vital in managing water resources, agriculture, industry, and flood management on the basin scale. In this...  相似文献   
92.
Kinetic studies of the catalytic steam gasification of Illinois No. 6 coal were carried out using binary and ternary eutectic salt mixtures in a fixed-bed reactor. The effects of major process variables such as temperature, pressure, catalyst loading and steam flow rate were evaluated for the binary 29% Na2CO3-71% K2CO3 and ternary 43.5% Li2CO3-31.5% Na2CO3-25% K2CO3 eutectic catalyst systems. A Langmuir-Hinshelwood rate expression was developed to explain the reaction mechanism for steam gasification using the binary and ternary catalysts. The activation energy of the ternary catalyst (98 kJ/mol) was less than that of the binary catalyst (201 kJ/mol) or single salt such as K2CO3 (170 kJ/mol). The molar heats of adsorption for the ternary and binary catalysts were exothermic and about 180 and 92 kJ/mol, respectively. The molten nature of the ternary eutectic at the gasification temperatures and its lower activation energy favored higher gasification rates compared to the single and binary alkali metal salts.  相似文献   
93.
This study explores the effect of annealing temperature and chemical composition on crystallographic texture evolution of commercially pure aluminium alloy sheets using response surface methodology (RSM). The orientation of the crystal structure in Euler space using Bunge notation has been studied to know the behavior of the metal and estimate its volume fraction. The experimental procedure involves texture analysis with respect to annealing temperature and chemical composition in correlation with the results of formability and use of RSM. The effect of important input parameters, namely, annealing temperature and chemical composition (impurities) was used for predicting the numerical models using the volume fraction of texture output from the crystallographic study using Design Expert 8.0.7.1, trial software. Also this study explains the effect of individual chemical components, namely, iron, silicon, and copper in evolution of texture components. The volume fraction of Cube {1 0 0} 〈0 0 1〉, Bs {1 1 0} 〈1 1 2〉, and S {1 2 3} 〈6 3 4〉 components increase, whenever iron and copper content increase and silicon component decreases.  相似文献   
94.
New class of aromatic bismaleimides containing anisyl group were synthesized from bis(4-amino 3,5-dimethyl phenyl) anisyl methane and maleic anhydride via bismaleamic acid as an intermediate followed by cyclodehydration to bismaleimides. The structure was confirmed by FTIR, 1H-NMR and elemental analysis. Further, a series of polyaspartimides were synthesized by addition reaction of bismaleimide (BMDA) with various diamines. The polymers were characterized by IR and elemental analysis. The polymers exhibit good solubility in organic solvents such as NMP, DMF and DMSO. They exhibit good thermal stability. T g of polyaspartimides are in the range of 125–278°C and T 10% weight loss are in the range of 398–476°C.  相似文献   
95.
96.
The study investigates the antifungal and antiaflatoxigenic efficacy of Lantana indica against Aspergillus flavus , a key storage fungus. The leaf essential oil of L. indica was found more active than leaf extracts. The oil absolutely inhibited the growth of A. flavus at 1.5 mg mL−1 while ethanolic and chloroform extracts of leaf show MIC at 7.5 and 10.0 mg mL−1 concentrations respectively. The oil also showed pronounced antiaflatoxigenic efficacy and completely inhibited the aflatoxin B1 production at 0.75 mg mL−1. The ethanolic and chloroformic extracts inhibited the aflatoxin B1 production at 5.0 and 7.5 mg mL−1, respectively while other extracts exhibited poor efficacy. The L. indica essential oil exhibited broad fungitoxic spectrum against twelve different storage moulds. The present findings may recommend the L. indica essential oil and its bioactive leaf extracts as natural preservative would of immense significance in view of the environmental and toxicological implications by indiscriminate use of synthetic pesticides .  相似文献   
97.
Mammography is the most widely used tool for the early detection of breast cancer. Computer-based algorithms can be developed to improve diagnostic information in mammograms and assist the radiologist to improve diagnostic accuracy. In this paper, we propose a novel computer aided technique to classify abnormalities in mammograms using fusion of local and global features. The objective of this work is to test the effectiveness of combined use of local and global features in detecting abnormalities in mammograms. Local features used in the system are Chebyshev moments and Haralick’s gray level co-occurrence matrix based texture features. Global features used are Laws texture energy measures, Gabor based texture energy measures and fractal dimension. All types of abnormalities namely clusters of microcalcifications, circumscribed masses, spiculated masses, architectural distortions and ill-defined masses are considered. A support vector machine classifier is designed to classify the samples into abnormal and normal classes. It is observed that combined use of local and global features has improved classification accuracy from 88.75% to 93.17%.  相似文献   
98.
Southern California is a diverse region that is home to a high concentration of food science companies, with an increasing demand for additional food scientists and technologists to join this workforce. Despite this abundance of food science companies and the high demand for jobs, there is currently a shortage in the number of qualified food scientists and technologists in the region. This shortage is also observed within higher education, with declining enrollments in the food science graduate and undergraduate programs across Southern California. Here, we conduct a case study to explore the factors that influence students from Southern California to pursue or not pursue careers in food science. We surveyed both undergraduate and graduate students currently enrolled in food science as well as industry professionals in the region to determine sources of knowledge about the discipline, and motivations and barriers for pursuing careers in food science. We also surveyed high school educators in the region to gain additional perspectives on how food science is being introduced at the secondary level, if at all. Our results demonstrate that many students and high school educators are not knowledgeable about career options within food science and that students who are pursuing food science largely report similar motivations for pursuing the discipline as those currently working in the food science industry. We conclude by discussing implications for the food science education community within Southern California and beyond.  相似文献   
99.
Functionalized surfaces with an affinity for albumin over competing serum proteins were prepared by immobilizing linear peptides or a small chemical ligand (SCL) with albumin-binding properties on silanized silicon surfaces. The real time adsorption of human serum albumin from single- and multi-component systems was monitored by dynamic ellipsometry. The experimentally obtained time-dependent adsorption data were analyzed by two models: a) a pseudo-first-order model and b) a biphasic kinetic model that accounted for the formation of tightly and loosely bound complexes. The biphasic kinetic model better fit the experimental data, and the binding constants were determined by non-linear regression analyses. The net forward rate constant for the tightly bound complex formation was distinctively higher for surfaces functionalized with peptides (~ 0.014 min− 1) when compared to surfaces functionalized with SCL (~ 10− 3 min− 1).  相似文献   
100.
Preparation of crack-free thin films of interconnected and non-agglomerated TiO2 nanoparticles on electronically conducting fluorine doped tin oxide surfaces is instrumental in designing and developing transparent dye-sensitized solar cells (DSCs). A novel technique called “Atomized Spray Pyrolysis” (ASP) has been designed and developed to achieve such perfectly transparent thin films. Optical transmittance of TiO2 films produced on FTO surface by this ASP method has been compared with those obtained by doctor-blading and by hand spray methods and found that the atomized spray pyrolysis technique give films with high transparency. Dye adsorption per gram of TiO2 is 2.16 times higher in the sample produced by the ASP method when compared to the film produced by the hand spray method and is 1.60 times higher than that produced by the doctor-blading method using a commercially available TiO2 nanocrystalline paste. SEM studies show the presence of interconnected discrete particles in the film produced by the ASP method. The fill factor (ff) remains almost constant for the cells with thickness from 6 μm to 13 μm but the highest photovoltage and photocurrent were found in ∼10 μm film based DSC which gave 8.2% conversion efficiency at AM 1.5 irradiation for cells of 0.25 cm2 active area.  相似文献   
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