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21.
Nitrogen use efficiency (NUE) in rice is low due to the inefficient management of fertilizer N by farmers. We evaluated a leaf color chart (LCC) as a simple tool for improving the time and rate of N fertilizer use in farmers’ fields for 4 years (2000–2003) in irrigated rice in northwestern India. Application of N fertilizer whenever leaf greenness was less than shade 4 on the LCC (the critical LCC value) produced rice grain yields on a par with blanket recommendation of applying 120 kg N ha−1 in three equal splits in different years, but it resulted in an average saving of 26% fertilizer N across villages and seasons. In most situations, there was no significant advantage of applying 20 kg N ha−1 as basal N at transplanting on grain yield and NUE of rice compared with no basal N. Use efficiencies of fertilizer N were higher when N was applied using LCC with a critical value of 4 than the recommended practice of applying 120 kg N ha−1 in three equal split doses on all sites and in all years. The LCC with a critical value of 4 for real-time N management can be efficiently used to increase NUE in all types of inbred rice cultivars presently popular with the farmers of the Indian Punjab. The LCC is a cheap and easy-to-use tool that allows real-time N management by farmers on a large area leading to improved fertilizer N use efficiency, and reduced risks associated with fertilizer N application.  相似文献   
22.
Poly(o-anisidine) (POA) is used as a modifier in an epoxy system to enhance its anticorrosive properties. The modification of POA is done by aminosilane to introduce amine functionality on the surface. Through this functionality, it becomes part of the coating backbone during curing of an epoxy-polyaminoamide system. The concentration of poly(o-anisidine) has been varied as 1, 3, and 5 wt%. Depolymerized product of polyethylene terephthalate (PET) obtained from aminolysis of PET with ethylamine has amine functionality. Depolymerized product is added at concentrations of only 1 and 3 wt%. The same concentration is used with 5 wt% of silane-modified POA. The synthesized POA and silane-modified POA (Si-POA) have been characterized by FTIR, UV–Visible, and XRD analysis. The coating is characterized by mechanical properties and it is observed that pencil hardness and scratch hardness of the coating were enhanced to 6H and 3.5 kg from 2H and 2.5 kg of a plain epoxy system. The anticorrosive properties of Si-POA are better as compared to plain POA, but the addition of depolymerized product is unable to improve the anticorrosive performance of the coating. In EIS study, it is observed that 5% Si-POA system shows the highest impedance > 10 G (Ω) and it has a tendency to retain anticorrosive performance for longer duration.  相似文献   
23.
BACKGROUND: Mungbean (Vigna radiata) is a major source of energy and protein in developing countries, especially for the vegetarian population. Improvement of the bioavailability of iron in mungbean by common household processes could make a significant contribution to the nutrition of people in countries where iron-deficiency anemia is widespread. OBJECTIVE: The study was conducted to determine the effect of common household processes on nutritional and antinutritional factors as well as in vitro bioavailability of iron in mungbean. METHODS: Mungbean was subjected to various domestic processes such as dehulling, pressure cooking, germination, and fermentation. The effects of these processes on proximate composition, antinutritional factors (phytin phosphorus, polyphenols, and neutral detergent), and iron, including ionizable iron, were determined. RESULTS: No significant change in crude protein content was observed. There was a significant (p < or = .05) increase in fiber content after germination. Ash content decreased significantly (p < or = .05) after all processing methods. The processing methods resulted in a significant (p < or = .05) reduction in phytin phosphorus and polyphenols. Pressure cooking significantly (p < or = .05) decreased the neutral detergent fiber, whereas fermentation and germination increased it. The phytate:iron molar ratio of processed mungbean revealed that the maximum reduction was in germinated and fermented samples. Ascorbic acid content increased significantly (p < or = .05) after germination. The in vitro bioavailability of iron in raw mungbean was 7.32%. All of the processing methods resulted in an increase in iron bioavailability in vitro; the maximum bioavailability was in germinated cooked mungbean (12.52%), followed by fermented cooked mungbean and germinated raw mungbean (both 11.04%). CONCLUSIONS: Suitable processing techniques can improve the in vitro bioavailability of iron from mungbean. If mungbean products with enhanced iron bioavailabilty are developed, they could help improve the iron status of the population.  相似文献   
24.
In addition to the benefits, increasing the constant need for antibiotics has resulted in the development of antibiotic bacterial resistance over time. Antibiotic tolerance mainly evolves in these bacteria through efflux pumps and biofilms. Leading to its modern and profitable uses, emerging nanotechnology is a significant field of research that is considered as the most important scientific breakthrough in recent years. Metal nanoparticles as nanocarriers are currently attracting a lot of interest from scientists, because of their wide range of applications and higher compatibility with bioactive components. As a consequence of their ability to inhibit the growth of bacteria, nanoparticles have been shown to have significant antibacterial, antifungal, antiviral, and antiparasitic efficacy in the battle against antibiotic resistance in microorganisms. As a result, this study covers bacterial tolerance to antibiotics, the antibacterial properties of various metal nanoparticles, their mechanisms, and the use of various metal and metal oxide nanoparticles as novel antibiotic carriers for direct antibiotic delivery.  相似文献   
25.
The formation of Fe3O4 nanoparticles by hydrothermal process has been studied. X‐ray Diffraction measurements were carried out to distinguish between the phases formed during the synthesis. Using the synthesized Fe3O4 nanoparticles, poly(vinyledene fluoride)‐Fe3O4 composite films were prepared by spin coating method. Scanning electron microscopy of the composite films showed the presence of Fe3O4 nanoparticles in the form of aggregates on the surface and inside of the porous polymer matrix. Differential Scanning calorimetry revealed that the crystallinity of PVDF decreased with the addition of Fe3O4. The conductitivity of the composite films was strongly influenced by the Fe3O4 content; conductivity increased with increase in Fe3O4 content. Vibration sample magnetometry results revealed the ferromagnetic behavior of the synthesized iron oxide nanoparticles with a Ms value of 74.50 emu/g. Also the presence of Fe3O4 nanoparticles rendered the composite films magnetic. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2011  相似文献   
26.
The aim of this study was to assess the biopotency of fermented food product Koozh associated coagulase-negative staphylococci (CNS) against Mycobacterium tuberculosis H37Rv and non-mycobacterial pathogens, and to document some technologically relevant attributes. The anti-tubercular property of six CNS strains was exhibited using luciferase reporter phage assay. All strains revealed pronounced mycobactericidal property in terms of higher percentage of relative light unit reduction (> 90%). The antagonistic role of CNS strains against non-mycobacterial pathogens was evaluated using agar well diffusion assay. Staphylococcus hominis strain MANF2 was found to be the most effective against Staphylococcus aureus MTCC 96 and Yersinia enterocolitica MTCC 840 with arbitrary units of 1600.31 ± 22.3 and 1500.23 ± 22.3 AU/mL, respectively. Further, various technological attributes of staphylococci were determined using standard methodology. All strains exhibited promising carbohydrate fermentation ability at standard in vitro conditions. CNS strains were positive for exopolysaccharide production and expressed strain specific lipase activity. All the isolates lacked amylase activity and biofilm formation ability. All six CNS strains, particularly strain MANF2 exhibited significant rate of autolytic and catalase activity, and showed the potential to reduce nitrate to nitrite. Most importantly, these strains were categorized for safe utilization based on in vitro safety hazards test. Overall, the present investigation indicated the persuasive biopotency of CNS against M. tuberculosis H37Rv and non-mycobacterial pathogens, and revealed adaptable technological attributes that would make them relevant for formulation of staphylococcal starter cultures for the development of quality fermented food products.  相似文献   
27.
We investigate the performance of 20-GHz radio over fibre (RoF) system having orthogonal frequency division multiplexed (OFDM) as radio signal using two modulation techniques – balanced detection for intensity modulation direct detection (IMDD) and coherent heterodyne detection suppressed carrier (SC) modulation. Dispersion-induced power fading is seen in conventional IMDD links due to the dependence of dispersion over frequency-dependent refractive index of the fibre. SC link is seen to compensate the power fading by terminating the direct current and even-order harmonics with the suppression of carrier along with balanced detection.  相似文献   
28.
Culture broths from Phanerochaete chrysosporium and Trametes cingulata, combined with co-factors such as hydrogen peroxide, dithiothreitol, copper, iron, and manganese ions were examined for the ability to modify lignin structure. High-performance size exclusion chromatography (HP-SEC) coupled to multi-angle laser light scattering (MALLS) detection was used to determine the effect of several white rot fungi, pH values, enzymes, and co-factors on the molecular weight distribution of treated kraft lignin. The analytical procedure tracked changes in molecular weight distribution, radius of gyration, and hydrodynamic radius. Results showed changes in the molecular weight distribution of lignin components when treated with combinations of factors. The induced cultures showed more lignin depolymerization for the specific lignin samples in which they were initially grown. The distribution in the radius of gyration became narrower with time, indicating that molecular conformation changed to a more uniform molecular shape. H2O2 and DTT showed the most significant changes in lignin molecular weight distribution.  相似文献   
29.
In this work, five methods for measuring the thickness of ultra-thin gate oxide layers in MOS structures were compared experimentally on n+ poly-SiO2-p-Si structures. Three methods are based on electrical capacitance-voltage (C-V) and current-voltage (I-V) data and the other two methods are HRTEM and optical measurement. MOS capacitors with oxide thickness in the range 17-55 Å have been used in this study. We found that thickness extracted using QM C-V and HRTEM agree within 1.0 Å over the whole thickness range when a dielectric constant of 3.9 was used. Comparison between thickness extracted using quantum interference (QI) I-V technique and optical measurement were also within 1.0 Å for thickness 31-47 Å. However, optical oxide thickness was consistently lower than the TEM thickness by about 2 Å over the thickness range under consideration. Both optical measurement and QM C-V modeling yield the same thickness as the nominal oxide thickness increases (>50 Å)  相似文献   
30.
The effect of varying concentrations of sodium chloride (0 to 2.5%), pH (5.8 to 4.2) and KBrO3 (75 ppm) with and without addition of L-cysteine ± HCI (25 to 75 ppm) on the baking of flours with high content of alphaamylase (108 to 540 SKB/100 g) was compared with a normal flour. Decreasing the pH of dough to 4.2 and increasing the salt concentration to 2.5% reduced the loaf volume and gluten recoveries considerably. Decreased pH also reduced the mixing tolerance of dough, which was counteracted by increased salt content of normal and high alpha-amylase flours. A combination of low pH, salt and L-cysteine ± HCI and 75 ppm of KBrO3 without sugar in the dough of higher alpha-amylase flour produced a satisfactory loaf by eliminating bulk fermentation.  相似文献   
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