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91.
The need for an LSI chip for interfacing data acquisition and conversion devices to a VME bus are highlighted. The functions of such an interface chip in a data acquisition subsystem are explained. The architecture, the design considerations and the novel features of the chip, designed at CEERI, Pilani, are discussed and the floor plan and specifications are indicated.  相似文献   
92.
Rowe L  Combs K  Deo S  Ensor C  Daunert S  Qu X 《Analytical chemistry》2008,80(22):8470-8476
Progress in the miniaturization and automation of complex analytical processes depends largely on increasing the sensitivity, diversity, and robustness of current labels. Because of their ubiquity and ease of use, fluorescent, enzymatic, and bioluminescent labels are often employed in such miniaturized and multiplexed formats, with each type of label having its own unique advantages and drawbacks. The ultrasensitive detection limits of bioluminescent reporters are especially advantageous when dealing with very small sample volumes and biological fluids. However, bioluminescent reporters currently do not have the multiplexing capability that fluorescent labels do. In an effort to address this limitation, we have developed a method of discriminating two semisynthetic aequorin variants from one another using time resolution. In this work we paired two aequorin conjugates with different coelenterazine analogues and then resolved the two signals from one another using the difference in decay kinetics and half-life times. Utilizing this time-resolution, we then developed a simultaneous, dual-analyte, single well assay for 6-keto-prostaglandin-FI-alpha and angiotensin II, two important cardiovascular molecules.  相似文献   
93.
Cloud computing is an upcoming and promising solution for utility computing that provides resources on demand. As it has grown into a business model, a large number of cloud service providers exist today in the cloud market, which further is expanding exponentially. Many cloud service providers, with almost similar functionality, pose a selection problem to the cloud users. To assist the users in the best service selection, as per its requirement, a framework has been developed in which users list their quality of service (QoS) expectation, while service providers express their offerings. Experience of the existing cloud users is also taken into account in order to select the best cloud service provider. This work identifies some new QoS metrics, besides few existing ones, and defines it in a way that eases both the user and the provider to express their expectations and offers, respectively, in a quantified manner. Further, a dynamic and flexible model, using a variant of ranked voting method, is proposed that considers users' requirement and suggests the best cloud service provider. Case studies affirm the correctness and the effectiveness of the proposed model. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
94.
ABSTRACT

The native Whiterocks (Utah) tar sand bitumen was separated into several boiling range fractions for detailed analysis and characterization. The lighter fraction (477-617 K) was evaluated for use as a transportation fuel and the residues (>617 K and >728 K) were evaluated for use as road asphalts. The 617 K plus residue from the Whiterocks bitumen can be classified as a viscosity grade AC-10 asphalt whereas the 728 K plus residue failed to meet asphalt specifications. Apart from the asphalt specification tests, several sophisticated techniques were used to characterize these fractions. The detailed structure of the low molecular weight portions of Whiterocks bitumen (477-617 K and 617-728 K) was determined by combined GC-MS. Several physical properties were also measured to evaluate the potential of the 477-617 K fraction as a high density/energy aviation turbine fuel. This lower molecular weight fraction of the bitumen contained predominantly naphthenic hydrocarbons and lesser concentrations of aromatic hydrocarbons. This was confirmed by the FTIR spectra and by the GC-MS analyses. As a result, the 477-617 K fraction appeared to be an excellent candidate as a feedstock for the production of high density, aviation turbine fuels following mild hydro treating. The heat of combustion, 135,500 BTU/gal., exceeded the specification for the high density/energy JP -11 aviation turbine fuel. The naphthenic hydrocarbons included alkylcyclohexanes, alkyldecalins, tricyclic terpanes, steranes, tetracyclic terpanes, and pentacyclic terpanes. The aromatic constituents were determined to be alkylbenzenes, benzomono-cycloparaffins, phenyl(cyclohexyl) alkanes, alkylnaphthalenes, benzodicycloparaffins, benzotricycloparaffins. alkylacenaphthenes, and naphthalene monocycloparaffins. These compounds were similar in nature to those found in the Green River shale oil.  相似文献   
95.
BACKGROUND: There is growing demand for the meat products having healthier characteristics. In an endeavour to develop low‐salt, low‐fat and high‐fibre chicken nuggets an investigation was carried out to observe the effects of partial replacement (40%) of sodium chloride in pre‐standardised low‐fat chicken nuggets (Control, 20 g kg?1 NaCl) with a salt substitute blend as well as incorporation of bottle gourd (Lagenaria siceraria L.) in the resulting low‐salt, low‐fat products at three different levels, i.e. 50, 75 and 100 g kg?1 (Treatments, 12 g kg?1 NaCl) on the various quality attributes. RESULTS: Sodium chloride replacement decreased (P < 0.01) emulsion and product pH, cooking yield, moisture, ash, yellowness, hue value and textural properties. pH values, moisture and dietary fibre increased (P < 0.01) while cooking yield, % protein, textural properties and total cholesterol were decreased with the incorporation of bottle gourd in low‐salt, low‐fat nuggets. Sensory attributes of the product were not affected with salt replacement; however, inclusion of bottle gourd at higher levels decreased (P < 0.05) flavour and texture scores. CONCLUSION: The results suggest that low‐salt, low‐fat and high‐fibre chicken nuggets can be developed with the use of a salt substitute blend and bottle gourd without affecting their acceptability. Copyright © 2012 Society of Chemical Industry  相似文献   
96.
Photofermentative hydrogen production is influenced by several parameters, including feed composition, pH levels, temperature and light intensity. In this study, experimental results obtained from batch cultures of Rhodobacter capsulatus DSM 1710 were analyzed to locate the maximum levels for the rate and yield of hydrogen production with respect to temperature and light intensity. For this purpose, a 3k general full factorial design was employed, using temperatures of 20, 30 and 38 °C and light intensities of 100, 200 and 340 W/m2. ANOVA results confirmed that these two parameters significantly affect hydrogen production. Surface and contour plots of the regression models revealed a maximum hydrogen production rate of 0.566 mmol H2/L/h at 27.5 °C and 287 W/m2 and a maximum hydrogen yield of 0.326 mol H2/mol substrate at 26.8 °C and 285 W/m2. Validation experiments at the calculated optima supported these findings.  相似文献   
97.
Present study reports treatment of simulated dairy wastewater (SDW) by inorganic coagulants such as poly aluminum chloride (PAC), ferrous sulphate (FeSO4) and potash alum (KAl(SO4)2·12H2O). Batch coagulation experiments were conducted to evaluate the influence of initial pH (pHi: 5–10) and coagulant dosage (m: 100–5000 mg/L) on chemical oxygen demand (COD) removal from SDW. Residual COD and system pH were observed as function of time. Optimum pHi (pHi,op) was found to be 8.0 for all the three coagulants. Optimum m (mop) was found to be 300, 800 and 500 mg/L for PAC, FeSO4 and KAl(SO4)2·12H2O, respectively, giving 69.2, 66.5 and 63.8% COD removal efficiency in 30 min. Heating values of the sludge generated by the coagulants PAC, FeSO4 and KAl(SO4)2·12H2O were found to be 20.7, 29.6 and 17.3 MJ/kg, respectively.  相似文献   
98.
This paper concerns the flow of an incompressible, viscous fluid past a porous spherical particle enclosing a solid core, using particle-in-cell method. The Brinkman’s equation in the porous region and the Stokes equation for clear fluid are used. At the fluid–porous interface, the stress jump boundary condition for the tangential stresses along with continuity of normal stress and velocity components are employed. No-slip and impenetrability boundary conditions on the solid spherical core have been used. The hydrodynamic drag force experienced by a porous spherical particle enclosing a solid core and permeability of membrane built up by solid particles with a porous shell are evaluated. It is found that the hydrodynamic drag force and dimensionless hydrodynamic permeability depends not only on the porous shell thickness, particle volume fraction γ and viscosities of porous and fluid medium, but also on the stress jump coefficient. Four known boundary conditions on the hypothetical surface are considered and compared: Happel’s, Kuwabara’s, Kvashnin’s and Cunningham’s (Mehta–Morse’s condition). Some previous results for the hydrodynamic drag force and dimensionless hydrodynamic permeability have been verified.  相似文献   
99.
Phase transformations, morphology, and crystallographic texture evolution in hot and cold-rolled Ti-25.51 wt.% Nb alloys are investigated. The experimental procedure involves synthesis of the alloy by arc melting followed by cold or hot rolling with intermediate prior and postheat treatments. Composition and phase analysis of all alloys are conducted using x-ray diffraction techniques and microstructural observations are conducted using an optical microscope. These examinations reveal that the as-melted alloy possesses large millimeter size grains with no stored strain energy and a two phase β ? α′ microstructure. Direct cold rolling followed by a short homogenization leads to a β ? α′′ mixture with ω precipitates. Two hour annealing before cold rolling leads to an α′ ? α′′ mixture with a characteristic triangular martensitic microstructure evidencing the act of shear on formation of the phase. Hot rolling followed by a water quench results in a β ? α′′ mixture, while annealing prior to hot rolling transforms the arc-melted material to a α′ ? α′′ mixture. The crystallographic textures of similar microstructure mixtures in hot and cold-rolled samples are distinctively different. The analysis shows that the microstructure serves as an identifying characteristic of the processing paths and is highly dependent on the mode of processing.  相似文献   
100.
Dyeing of cotton and jute with tea as a natural dye   总被引:7,自引:0,他引:7  
Cotton and jute fabrics were dyed with an aqueous extract of tea, containing tannins as the main colorant species. The dyeing was carried out with and without metal salts as mordants, using three different dyeing methods: pre-mordanting, meta-mordanting and post-mordanting. The resulting wash and light fastnesses of the dyed fabrics were good to excellent. The colour of the fabrics was investigated on computer colour matching system in terms of K/S , and CIELAB colour-difference values. Deep shades ( K/S = 3.9) were obtained for jute in acidic media, while cotton fabrics could be dyed in medium depths ( K/S = 2.0) under identical conditions of dyeing.  相似文献   
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