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61.
Tapioca and maize are the major sources of starch in India. Tapioca starch is produced in very small units which are not extensively mechanized. This quality of the starch produced is not of a high quality. Maize starch is produced in mechanized units. The liberalization of the economy and growing consumerism bode well for the starch industry in India. Growth of the starch industry would depend on developing applications for starch as well as optimizing usage to derive maximum benefits. The unique properties of maize and tapioca should be considered.  相似文献   
62.
An incremental development of the Mondex system in Event-B   总被引:2,自引:1,他引:1  
A development of the Mondex system was undertaken using Event-B and its associated proof tools. An incremental approach was used whereby the refinement between the abstract specification of the system and its detailed design was verified through a series of refinements. The consequence of this incremental approach was that we achieved a very high degree of automatic proof. The essential features of our development are outlined. We also present some modelling and proof guidelines that we found helped us gain a deep understanding of the system and achieve the high degree of automatic proof. J. C. P. Woodcock  相似文献   
63.
The recent discovery of ferromagnetism above room temperature in low-temperature-processed MnO(2)-ZnO has generated significant interest. Using suitably designed bulk and thin-film studies, we demonstrate that the ferromagnetism in this system originates in a metastable phase rather than by carrier-induced interaction between separated Mn atoms in ZnO. The ferromagnetism persists up to approximately 980 K, and further heating transforms the metastable phase and kills the ferromagnetism. By studying the interface diffusion and reaction between thin-film bilayers of Mn and Zn oxides, we show that a uniform solution of Mn in ZnO does not form under low-temperature processing. Instead, a metastable ferromagnetic phase develops by Zn diffusion into the Mn oxide. Direct low-temperature film growth of Zn-incorporated Mn oxide by pulsed laser deposition shows ferromagnetism at low Zn concentration for an optimum oxygen growth pressure. Our results strongly suggest that the observed ferromagnetic phase is oxygen-vacancy-stabilized Mn(2-x)Zn(x)O(3-delta.).  相似文献   
64.
Response surface methodological studies of growth parameters for carotenoid production by a mutant strain of Rhodotorula gracilis (CFR 0-1) was carried out by a two-level fractional factorial design involving five variables, namely glucose concentration (%), incubation period (days), volume of inoculum (ml/100 ml), pH, and temperature (°C). The response equation developed indicated linear relationship between period of incubation, temperature, sugar concentration, and volume of inoculum on carotenoid production. A temperature of 24 °C was found to exhibit maximum carotenoid production in the mutant. The results indicated maximum carotenogenesis (0.09%) at 8% glucose level, with pH 7.5 and 6.0 ml/100 ml of inoculum for an incubation period of 12 days at 24 °C, which was also verified by experimental data.  相似文献   
65.
The development of the fabrication technology of macro-brush configuration of tungsten (W) and carbon (graphite and CFC) plasma facing components (PFCs) for ITER like tokamak application is presented. The fabrication of qualified joint of PFC is a requirement for fusion tokamak. Vacuum brazing method has been employed for joining of W/CuCrZr and C/CuCrZr. Oxygen free high conductivity (OFHC) copper casting on W tiles was performed followed by machining, polishing and ultrasonic cleaning of the samples prior to vacuum brazing. The W/CuCrZr and graphite/CuCrZr based test mockups were vacuum brazed using silver free alloys. The mechanical shear and tensile strengths were evaluated for the W/CuCrZr and graphite/CuCrZr brazed joint samples. The micro-structural examination of the joints showed smooth interface. The details of fabrication and characterization procedure for macro-brush tungsten and carbon based PFC test mockups are presented.  相似文献   
66.
This laboratory study aimed to enhance the adhesion strength of resin cement to zirconia by infusing carbon nanotubes (CNTs) in experimental silane primers. Eighteen ZrO2 blanks were pretreated with Rocatec? Soft, and divided into six groups: Group 1: Monobond® S silane (control); Group 2: 0.5 wt.% single-walled CNTs blended Monobond® S; Group 3: 0.5 wt.% multiple-walled CNTs blended Monobond® S; Group 4: a blend of 1.0 vol.% 3-acryloxypropyltrimethoxysilane (ACPS) + 0.5 vol.% bis-1,2-(triethoxysilyl)ethane (BTSE); Group 5: 0.5 wt.% single-walled CNTs blended in 1.0 vol.% ACPS + 0.5 vol.% BTSE; and Group 6: 0.5 wt.% multiple-walled CNTs blended in 1.0 vol.% ACPS + 0.5 vol.% BTSE. Next, resin composite stubs were prepared on treated ZrO2 surfaces. The specimens were stored in distilled water at 37°C ± 2°C for 2 months and 4 months. According to analysis of variance (ANOVA) and Tukey’s post hoc test (n = 10, α = 0.05), the highest enclosed mold shear bond strength (EM-SBS) value was observed in Group 5 (20.5 MPa ± 8.0 MPa) at the end of 4 months. Experimental silane primer containing a blend of 1.0 vol.% ACPS and 0.5 vol.% BTSE with infused single-walled CNTs might significantly enhance resin cement adhesion to silica-coated ZrO2.  相似文献   
67.
The effects of β-cyclodextrin (BCD) and reaction time on the recovery of cholesterol from egg yolk were studied at 25°C based on response surface methodology. The developed response model is of the form: Y = 5.585 + 429.77 X c + 0.534 X t 2, where Y is the predicted cholesterol recovery (%), X c is the BCD/egg yolk ratio (kg/kg) and X t is the reaction time (h). Cholesterol recovery increased with the both BCD/egg yolk ratio and reaction time and there was no optimum value. The model predicted a cholesterol recovery of 94.5% at a BCD/egg yolk ratio of 0.163 over a reaction time of 6 h whereas experiments showed a cholesterol recovery of 87.7%.  相似文献   
68.
The X-ray diffraction Rietveld refinement of Ba[(Fe1−xCox)1/2Nb1/2]O3 with 0 ≤ X ≤ 1 shows cubic structure formation with space group Pm3m. No distinct tilting of oxygen octahedron is observed. The dielectric measurement of such a cubic system exhibited giant values (?′ > 104) in the temperature range of 298-483 K and frequency range of 102-105 Hz. An analysis of the permittivity, electric modulus, and electrical conductivity properties in these systems confirmed the presence of oxygen vacancies induced dipolar relaxation. Our investigations show that the observed extremely high dielectric constant values are predominantly the result of oxygen vacancies induced dipoles produced at the grain boundaries. Additional significant intrinsic contributions to the permittivity comes from the directly doped electrons at the unit cell, as indicated by the enhancement in the observed values of the permittivity on replacement of Fe3+ (3d5) by Co3+ (3d6). The contributions of the doped free charges and the oxygen vacancy induced dipoles are separated using the Jump Relaxation Model.  相似文献   
69.
Abstract: Powdered infant formula has previously been linked to the transmission of various bacterial pathogens in infants resulting in life‐threatening disease and death. Survival studies of 2 common foodborne pathogens, Salmonella enterica serovar Typhi and Shigella dysenteriae, in powdered infant formula have not been previously studied despite the potentially devastating consequences from ingestion of these organisms, particularly by newborns, in case of a natural or deliberate contamination event. Therefore, to better predict the risk of S. Typhi and S. dysenteriae infection from consumption of infant formula, the present study was undertaken to determine survival of these microorganisms in dry infant formula under varying atmospheric conditions. A 2‐strain cocktail of S. Typhi and a 3‐strain cocktail of S. dysenteriae were stored for up to 12 wk in dehydrated infant formula in an ambient air or nitrogen atmosphere. Viable counts of S. Typhi at 12 wk in infant formula revealed a 2.9‐ and 1.69‐log decrease in ambient air and nitrogen atmosphere, respectively. Viable counts of S. dysenteriae at 12 wk in infant formula revealed a 0.81‐ and 0.42‐log decrease in ambient air and nitrogen atmosphere, respectively. These results show that S. Typhi and S. dysenteriae can remain viable for prolonged periods of time in powdered infant formula, and the presence of nitrogen enhances survival. Practical Application: Our goal in this work was to study the survival of S. Typhi and S. dysenteriae in dehydrated storage conditions in infant formula. This interest is partially generated by the possibility of using these 2 microorganisms to deliberately contaminate the food supply. The outcome of this study will help us to have a better idea how to respond and react to the risk of deliberate food contamination.  相似文献   
70.
Qualification of tungsten (W) and graphite (C) based brazed plasma facing components (PFCs) is an important R&D area in fusion research. Pre-qualification tests for brazed joints between W–CuCrZr and C–CuCrZr using NDT (IR thermography and ultrasonic test) and thermal fatigue test are attempted. Mockups having good quality brazed joints of W and C based PFCs were identified using NDT. Subsequently, thermal fatigue test was performed on the identified mockups. All brazed tiles of W based PFC mockups could withstand thermal fatigue test, however, few tiles of C based PFC mockup were found detached. Thermal analyses of mockups are performed using finite element analysis (ANSYS) software to simulate the thermal hydraulic condition with 10 MW/m2 uniform heat flux. Details about experimental and computational work are presented here.  相似文献   
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