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Sensory quality and storage stability of blueberry juice blends were investigated with the goal of maintaining dominant blueberry flavor, aroma and color. Apple juice, Concord and Venus grape juices and cranberry juice cocktail were blended at 75, 50 and 25% with blueberry juice. As the percent of blueberry juice decreased, the intensity of blueberry‐related sensory attributes decreased. The 25% Concord and Venus blends were the only blends that resulted in blueberry flavor similar to the reference. Apple and cranberry juice cocktail blended with blueberry juice produced several blends with good flavor and aroma, but they were not readily characterized as blueberry juice. All blends at the 25% level produced blueberry color equal to or greater than the reference. The juice samples were evaluated initially and after three months of storage at 37C. After storage, all blends had decreased red color. 相似文献
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RENEE THRELFALL GARY MAIN JUSTIN MORRIS 《Australian Journal of Grape and Wine Research》2006,12(2):161-169
Juices from grape samples subjected to two storage methods (fresh and frozen) and two post-homogenisation treatments (21o C and 71o C) were examined for extraction of grape berry components and compared to a microvinified wine made from the same lot of fresh grapes. Cabernet Franc ( Vitis vinifera ) and Cynthiana ( Vitis aestivalis ) grapes were evaluated in 2003. Cabernet Franc, Cabernet Sauvignon ( Vitis vinifera ), Chambourcin (interspecific hybrid) and Cynthiana grapes were evaluated in 2004. Fresh grapes from each variety were sampled, analysed and prepared for microvinification. Frozen grapes of all varieties were thawed and analysed at the same time. For all varieties in both years, heating the must of fresh or frozen grapes increased the titratable acidity (11–58%), tartaric acid levels (12–110%), potassium content (15–62%), darkness (31–97%), red colour (54–1517%) and total red pigment values (36–1171%) of juice as compared to the juice from unheated must. For all varieties in 2004, heating the must from fresh or frozen grapes increased total phenolics (43–619%) of juice as compared to the juice from unheated must. Compared to fresh grape processing, freezing the grapes and then processing at 21o C or 71o C had varying results (increases and decreases) regarding the extraction of components in all varieties and both years but usually provided juice with composition most similar to that of the red wine produced by microvinification. Although the degree of extraction of individual components in the juice is influenced by selection of grape storage and must processing procedures, consistency of handling and procedure provided consistent results with low variability. 相似文献
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Methods for the study of the stratum corneum in situ are described and their application to clinical problems and cosmetic science are discussed. In vivo measurements of the thickness of skin and the components of skin can be made using high frequency pulsed ultrasound. Improved resolution of the device should allow measurement of epidermal thickness, and even that of the stratum corneum, which may vary with hydration. The protective ability of the stratum corneum can be estimated in a number of ways, the most familiar technique being transepidermal water loss measurements. Mechanical properties of the stratum corneum have been widely investigated in vivo by numerous researchers. A recent technique devised by us to deform the stratum corneum using an extendable metal frame has been used on patients with ichthyotic disorders. The deformation or compliance of the skin surface has been measured using profilometric methods, and compared to normal individuals. The results appear to be in agreement with the loss of flexural ability experienced by ichthyotic patients. Other mechanical methods more usually involve the measurement of the forces generated by skin while undergoing extension. Three techniques are described which have been used to investigate hydrational change with emollient application. Finally, the phenomenon of desquamation is discussed and methods presented for its evaluation. Passive collection of corneocytes using chambers is useful for estimation of the rates of desquamation, but are laborious and inconvenient. Forced desquamation using the desquamator enables rapid controlled harvesting of corneocytes. In addition to this, the dansyl chloride fluorescence technique has been adopted for estimation of stratum corneum kinetics using visual comparison and fluorimetric techniques. These techniques require further refinement and validation, but the tests available now are nonetheless important in understanding the biology and pharmacology of the stratum corneum. 相似文献
68.
JEFFRI C. BOHLSCHEID XIAO-DONG WANG D. SCOTT MATTINSON CHARLES G. EDWARDS 《Journal of food quality》2006,29(1):1-15
A modified headspace solid phase microextraction (HS‐SPME) method was compared with Amberlite® XAD‐2 resin for the extraction of volatile compounds. In the HS‐SPME method, volatiles were extracted using an 85 μm polyacrylate fiber from wines that contained a standardized amount of ethanol (10% v/v), NaCl (0.325 g/mL) and internal standards (dodecanol and nonanoic acid). Both extraction procedures yielded high relative recoveries (>92%) and reproducibilities (coefficient of variations ≤ 11%) for the different higher alcohols, esters and medium‐chain fatty acids. Overall, limits of detection for the HS‐SPME and XAD‐2 methods were below sensory threshold concentrations. HS‐SPME and XAD‐2 performed similarly in the analysis of a Riesling wine; however, the HS‐SPME method did not require organic solvents and was generally quicker to perform. In applying the HS‐SPME method, differences in concentrations of volatile compounds produced in Riesling and Chenin blanc wines by 11 different yeast strains were noted. 相似文献
69.
GARY S. SPRING 《Computer-Aided Civil and Infrastructure Engineering》1988,3(4):299-309
The detailed analysis of highway locations that have been identified as hazardous within the framework of a state Highway Safety Improvement Program (HSIP) requires a great deal of time and money to perform. Given the limited resources available to state highway agencies, whose task it is to perform such analyses, it seems a worthwhile effort to automate this "location analysis." And, given the nature of location analysis problems, which are based on judgement rather than mathematical models, it was known a prior; that conventional automation techniques were not appropriate for this application. A prototype microcomputer-based expert system, which performs location analysis, was developed to assess the feasibility of applying this new technology to location analysis problems. This paper describes the prototype system, and presents a brief discussion of some of the issues that were addressed when building the system. 相似文献
70.
The nature of stresses in hot-filament chemical vapour deposited diamond thin films on WC substrates
The nature of film stresses in hot-filament chemical vapour deposited (HFCVD) diamond thin films on tungsten carbide substrates, is reported. Commercial WC substrates were subjected to various surface treatments. Subsequently, they were coated with a diamond film and examined for stresses using X-ray diffraction. All but one of the stress measurements indicated various levels of compressive stresses in the film and at the film–substrate interface. These stresses are compared with those obtained by other researchers. Intrinsic film stresses were also computed for diamond films and found to be tensile. WC drills, of 0.125 in. diameter, were also diamond coated and the stress levels measured along drill flanks and flutes. Significant variations were found in these stresses, and the results were analysed from a film–substrate adhesion perspective. 相似文献