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1.
Packaging represents a significant and expensive obstacle in commercializing microsystem technology (MST) devices such as microelectromechanical systems (MEMS), microopticalelectromechanical systems (MOEMS), microsensors, microactuators, and other micromachined devices. This paper describes a novel wafer-level protection method for MSTs which facilitate improved manufacturing throughput and automation in package assembly, wafer-level testing of devices, and enhanced device performance. The method involves the use of a wafer-sized microcap array. This array consists of an assortment of small caps molded onto a material with adjustable shapes and sizes to serve as protective structures against the hostile environments associated with packaging. It may also include modifications which enhance its adhesion to the MST wafer or increase the MST device function. Depending on the application, the micromolded cap can be designed and modified to facilitate additional functions, such as optical, electrical, mechanical, and chemical functions, which are not easily achieved in the device by traditional means. The fabrication and materials selection of the microcap device is discussed in this paper. The results of wafer-level microcap packaging demonstrations are also presented. 相似文献
2.
In an attempt to validate the use of topographical mapping of EEG as a method of localising cerebral function, EEG was recorded during a simple motor task. A minimum of 20 sec artifact-free EEG was recorded from 24 healthy right handed subjects in each of 4 conditions: eyes open 1, motor task (left/right, order randomized), eyes open 2. EEG amplitude maps were computed in delta, theta, alpha, and beta (1 and 2). Differences were seen between the eyes open and the motor conditions in alpha, beta 1 and beta 2 localised to the motor and supplementary motor areas. It is argued that topographical mapping of EEG is a valid method of localising cognitive function in healthy individuals for the Luria task. 相似文献
3.
Alicja egota Stefania Bachman 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1987,184(1):3-7
Summary The effect of irradiation on the nonenzymatic browning reaction in the model system consisting of 0,03M-fructose, 0.01M-alanine and 0.01M-phenylalanine in aqueous solution was investigated. The loss of phenylalanine and fructose after irradiation, due to their high reactivity towards radical species of water radiolysis was greater compared with alanine. The heating of preirradiated solution caused only a slight decrease in the concentration of substrates. The characteristic absorption spectra for only irradiated and for irradiated and heated solutions were recorded. The heating produced a chromophore with a broadened absorption maximum about 285 nm. Two unidentified Amadori type compounds which gave positive response to ninhydrin were found by amino-acid analysis.
For part 3 see [8] 相似文献
Durch -Strahlung induzierte nichtenzymatische Bräunung im Modell-System Teil IV. Dreikomponentenmodellsystem aus Fructose, Alanin und Phenylalanin
Zusammenfassung Es wurde der Einfluß von -Strahlen auf die nichtenzymatische Bräunung im Dreikomponenten-Modellsystem, bestehend aus 0,03m-Fructose, 0,01m-Alanin und 0,01m-Phenylalanin in wäßriger Lösung untersucht. Der Verlust an Phenylalanin und Fructose nach der Bestrahlung war größer als bei Alanin wegen dessen größerer Reaktivität zu den Radikalen der Wasserradiolyse. Beim Erhitzen von bestrahlten Losungen wurde eine Abnahme in der Konzentration von Substraten beobachtet. Es wurden die charakteristischen Absorptionsspektren von lediglich bestrahlten und von bestrahlten und gleichzeitig erhitzten Lösungen aufgenommen. Beim Erhitzen wird ein Chromophor mit breitem Absorptionsmaximum bei ungefähr 285 nm, gebildet. Es wurden zwei nichtidentifizierte Amadoriprodukte mit positiver Ninhydrin-Reaktion bei den Aminosäureanalysen gefunden.
For part 3 see [8] 相似文献
4.
Oyster tissue contained 2.4% lipid, 0.14 μmole aldehyde per milligram lipid and at least 10 μg phosphorous per milligram lipid.
The neutral lipid represented 58%, the glycolipid 6%, and the polar lipid 36% of the total lipid recovered after silicic acid
column chromatography. Aldehydes were found in all fractions, but the presence of plasmalogen was verified in only the neutral
and polar lipid fractions. At least 68% of the plasmalogen in oyster lipid was found in the polar lipid fraction. At least
13% of the phosphorous in oyster lipids was present as phosphonolipid. The distribution of phosphate and phosphonate lipids
was: diacyl phospholipid 38.1%, plasmalogen phospholipid 21.8%, sphingophosphonolipid 13.5%, glyceryl ether phospholipid 8.3%,
sphingophospholipid 6.9%, plasmalogen phosphonolipid 6.4%, diacyl phosphonolipid 2.6%, and glyceryl ether phosphonolipid 2.4%.
When the per cent of phosphorous as phosphonolipid within the plasmalogen and glyceryl ether classes was calculated, similar
values were obtained. These results support the hypothesis that there is a product precursor relationship between these two
classes of lipids.
Some of the data taken from a thesis to be submitted to the Graduate School, University of Maryland, by Leslye Johnson in
partial fulfillment of the requirements for the M.S. degree in biochemistry. 相似文献
5.
Sae Hoon Kim Timothy B. Neuschwander Brandon R. Macias Larry Bachman Jr. Alan R. Hargens 《Applied ergonomics》2014
Heavy backpacks are often used in extreme environments, for example by military during combat, therefore completion of tasks quickly and efficiently is of operational relevance. The purpose of this study was to quantify hemodynamic parameters (brachial artery Doppler and microvascular flow by photoplethysmography; tissue oxygenation by near-infrared spectroscopy; arterial oxygen saturation by pulse oximeter) and sensation in upper extremities and hands (Semmes-Weinstein monofilament test and 2-point discrimination test) while wearing a loaded backpack (12 kg) in healthy adults for 10 min. All values were compared to baseline before wearing a backpack. Moderate weight loaded backpack loads significantly decreased upper extremity sensation as well as all macrovascular and microvascular hemodynamic values. Decreased macrovascular and microvascular hemodynamics may produce neurological dysfunction and consequently, probably affect fine motor control of the hands. 相似文献
6.
Leonard R. Bachman 《Building Research & Information》2013,41(6):752-760
Definitions and perceptions of professionalism are continually challenged and transformed by public need, government interaction and institutional organizations. When the goals of those three entities are focused on near-term results, this poses a significant threat to the integrity, value and relevance of professional services. When the individual and corporate professional's profit margin, corporate shareholder responsibility and news media sensationalism are factored in, this short-termism dynamic is greatly magnified. Built environment professions are seen as particularly vulnerable to this threat, given that investments in buildings and infrastructure have long-life and high-performance service expectations. This commentary responds to the Building Research & Information special issue entitled ‘New Professionalism’ (2013, volume 40, number 1) and situates the predicament of built environment professionals within an emerging historical transition: that of the post-industrial information society with its characteristic knowledge workers and cybernetic bases of production. Long-term virtues of the built environment mission such as sustainability, public good and evidence-based design are shown to be reflections of the transition from industrial era short-termism to post-industrial systemic foresight. This commentary supplements the special issue papers with a discussion on the broader academy's potential role in breaking the stranglehold of contemporary short-termism in the built environment professions. 相似文献
7.
Several recent foodborne disease outbreaks associated with leafy green vegetables, including spinach, have been reported. X-ray is a non-thermal technology that has shown promise for reducing pathogenic and spoilage bacteria on spinach leaves. Inactivation of inoculated Escherichia coli O157:H7, Listeria monocytogenes, Salmonella enterica and Shigella flexneri on spinach leaves using X-ray at different doses (0.1, 0.2, 0.3, 0.5, 0.75, 1.0, 1.5 and 2.0 kGy) was studied. The effect of X-ray on color quality and microflora counts (mesophilic counts, psychrotrophic counts and yeast and mold counts) of untreated and treated spinach was also determined. A mixture of three strains of each tested organism was spot inoculated (100 μl) onto the surface of spinach leaves (approximately 8–9 log ml−1), separately, and air-dried, followed by treatment with X-ray at 22 °C and 55–60% relative humidity. Surviving bacterial populations on spinach leaves were evaluated using a nonselective medium (tryptic soy agar) with a selective medium overlay for each bacteria; E. coli O157:H7 (CT-SMAC agar), L. monocytogenes (MOA), and S. enterica and S. flexneri (XLD). More than a 5 log CFU reduction/leaf was achieved with 2.0 kGy X-ray for all tested pathogens. Furthermore, treatment with X-ray significantly reduced the initial inherent microflora on spinach leaves and inherent levels were significantly (p < 0.05) lower than the control sample throughout refrigerated storage for 30 days. Treatment with X-ray did not significantly affect the color of spinach leaves, even when the maximum dose (2.0 kGy) was used. 相似文献
8.
Incipient pay-for-performance (P4P) plans offer to improve the quality of general medical care, but they have not yet begun to influence clinical outcomes in the behavioral health care arena. Following a brief review of the quality chasm in behavioral health care and some initial applications of P4P programs, this article presents 2 bird's-eye view proposals with which the primary and behavioral specialty care sectors of the American health care system can begin to design and implement P4P incentives. Discussion of the value of behavioral health care, the Provider Quality Index, P4P implementation issues, implications for practicing psychologists, and some cautionary notes conclude the article. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
9.
The recently published 1994 National Earthquake Hazards Reduction Program (NEHRP) provisions include new and substantially improved provisions for the seismic design of nonstructural components, including architectural, mechanical, and electrical components. The provisions are a significant departure from the 1991 NEHRP provisions and other seismic provisions, such as those offered by the 1994 Uniform Building Code (UBC). The design-force provisions are rationally derived and consider actual in-structure acceleration data recorded in recent significant California earthquakes. Also considered in the design-force equations are the dynamic properties of the components, the location of the component within the supporting structure, the safety and operational importance of the component, and the component's anchorage ductility and energy-absorption capability. The resulting force requirements of the new recommendations are compared with the 1991 NEHRP provisions and the 1994 UBC requirements. In addition, explicit design displacement provisions are introduced and discussed. 相似文献
10.
Phasic changes in cardiac reactivity to innocuous stimuli, presented in a sensory disparity paradigm, were used to evaluate habituation and learning processes in five decerebrate subjects. Three subjects showed systematic changes over trials in the pattern of cardiac response to simple auditory or visual stimuli, indicative of habituation. In addition, tests for associative learning were given after repeated presentations of two paired stimuli. The appearance of a marked cardiac orienting response, to the unpredictable omission of the second stimulus, documented the development of a conditioned association in these same three subjects. One additional subject failed to show a consistent pattern of response to the stimuli, and another demonstrated a consistent response which was not subject to habituation. Overall, these findings support the view that learning processes are not solely the product of the cerebral hemispheres, but reflect general integrative features of the human neuraxis. 相似文献