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排序方式: 共有517条查询结果,搜索用时 15 毫秒
81.
PAUL R. PETRIE NICOLA M. COOLEY PETER R. CLINGELEFFER 《Australian Journal of Grape and Wine Research》2004,10(3):203-215
Given their perennial nature, grapevines can respond to deficit irrigation during both the current season as well as during the following season, even though full irrigation may have been restored during that second season. To define the cropping responses involved, three post-veraison irrigation treatments were imposed on spur, mechanically and minimally pruned Shiraz vines that were already receiving restricted water application using Partial Rootzone Drying (PRD). The treatments resulted in the vines receiving 1.25 ML per hectare pre veraison and the three irrigation treatments receiving 1.25, 0.65 and 0 ML of water per hectare in the post-veraison period. Water deficit during the current season reduced berry and bunch weight, and yield. Sugar concentration was reduced, and phenolic concentration increased when less water was applied, but anthocyanin concentration was unaffected. Although irrigation was returned to standard practice (PRD) in the following season, yield was reduced in accordance with deficit irrigation treatments the previous season. This reduction in yield was primarily caused by fewer bunches per vine, which in turn was a direct consequence of fewer shoots per vine (lower budburst). The lower crop load on the vines that had received restricted irrigation post-veraison in the previous season resulted in higher sugar and antho-cyanin concentrations in fruit the following season. Lighter pruning resulted in a greater number of smaller bunches comprising smaller berries. In both seasons the minimal pruning treatment delayed fruit maturity as measured by sugar accumulation. Post-veraison water deficit thus has the potential to impact on both yield and fruit composition during the current season as well as during the subsequent season. 相似文献
82.
FRANCESCO PADUANO EMANUELA ALTOMARE BENEDETTA MARRELLI VINCENZO DATTILO HAIZAL MOHD HUSSAINI PAUL ROY COOPER MARCO TATULLO 《Biocell》2022,46(8):1827-1835
Oral Cancer (OC) is one of the most recurrent cancers in the head and neck squamous cancer (SCCHN)category. Recently, the genome-wide association studies (GWAS) have gained growing interest in the scientificcommunity. GWAS have identified several pathways involved in the interactions among general risk factors andgenomic variants affecting SCCHN. This systematic overview aims to critically evaluate the latest data reported withinthe scientific literature. The aim was to investigate the impact of genetic aspects on SCCHN onset and prognosis,involving other clinical and systemic co-factors. PubMed, Google Scholar, and Cancer Genetics Web databases havebeen systematically investigated for original articles published in the last two years, reporting studies on the mainqueries addressed in this work. This review also comparatively describes the impact of environmental andpathological co-factors in different types of cancers, clarifying and updating the role of genetic factors in SCCHNonset and development. The main outcomes reported may be helpful to drive clinicians towards their clinicalevaluations for the most appropriate therapeutic approach in SCCHN. 相似文献
83.
PAUL M. BOBROWSKI 《国际生产研究杂志》2013,51(11):1935-1948
The scheduling literature has developed two almost mutually exclusive problems; a static and a dynamic scheduling problem. The result has been that different tools have been developed to solve each problem. In this research, a model is developed such that it contains elements of both the static and the dynamic problems. This model, called here the discrete release model, considers the routing, loading, and release decisions as well as the customary sequencing decision evident in most job shop research. The objective of the research is to implement a method for examining tentative loading assignments prior to their release to the shop floor. The research develops a single pass, sequential routing and loading system. A heuristic is then developed that will enable jobs to be reloaded and rerouted prior to their start of processing. The system is tested in various shop environments to ascertain the effectiveness of this loading heuristic. 相似文献
84.
This paper investigates the flow field and particle trajectories in the GE90 pyrometer purge air design in order to illustrate the fouling mechanism that drives the deposition of particulates onto the lens. It is shown that the predominant flow feature within the purging system is a swirl pattern that develops at the mouth of the unit's still tube. This feature has the ability to draw contaminant particles into the still tube and thus significantly increase the likelihood of particle deposition resulting in optical fouling of the pyrometer's optics. 相似文献
85.
Modern high performance adhesives are designed to offer an optimized balance of elasticity,toughness and plastic deformation capacity for the individual fields of application in e.g. the building and construction or transportation and vehicle industry. The long-term life prediction for adhesive joints based on laboratory tests requiring only days,weeks,or months is still a demanding challenge. Testing in practice is carried out with the intention of accelerating time dependent aging effects that may occur in a bonded joint during its service time. Initial strength values of bonded joints,such as shear or peel properties can often be obtained from the adhesive manufacturers or retrieved from literature. They are useful to compare different adhesives and to demonstrate the effect of parameters such as bond line thickness,overlap length or curing conditions,and,in some cases,the surface state. On the other hand only few data are available describing the mechanical long-term properties of adhesives related to creep and relaxation under static load conditions. Due to the nature of the polymer network of organic adhesives their viscoelastic-plastic deformation behavior is strongly time-and temperature dependent. The objective of this paper is to illustrate effective methods for investigating and predicting the creep and relaxation properties of adhesively bonded joints in the long-term region and for creating basic data for the design and engineering with adhesives. 相似文献
86.
MICROALGAE AS A SOURCE OF FATTY ACIDS 总被引:2,自引:0,他引:2
Microalgae are a very diverse group of organisms that consist of both prokaryotic and eukaryotic forms. Although most microalgae are phototrophic, some species are also capable of heterotrophic growth. Some species of microalgae can be induced to overproduce particular fatty acids through simple manipulations of the physical and chemical properties of the culture medium. As a result of the profound differences in cellular organization and growth modes and the ability to manipulate their fatty acid content, microalgae represent a significant source of unusual and valuable lipids and fatty acids.
The utilization of microalgal lipids and fatty acids as food components requires that these organisms be grown at large scale under controlled conditions. Several growth systems have been developed for large scale growth of phototrophic microalgae using either natural sunlight or artificial light, but their lack of control of culturing parameters or their high cost of operation have limited their utility for the production of food products. Instead, large scale cultivation of heterotrophic microalgae using classical fermentation systems provides consistent biomass produced under highly controlled conditions at low cost.
Microalgae contain many of the major lipid classes and fatty acids found in other organisms. However, they are also the principal producers in the biosphere of some polyunsaturated fatty acids, especially docosahexaenoic acid (DHA). The high DHA content found in some algae is currently being utilized to supplement infant formula to enable it to more closely resemble human breast milk. Thus, the commercialization of DHA from microalgae demonstrates the value of these organisms as a source of useful fatty acids. 相似文献
The utilization of microalgal lipids and fatty acids as food components requires that these organisms be grown at large scale under controlled conditions. Several growth systems have been developed for large scale growth of phototrophic microalgae using either natural sunlight or artificial light, but their lack of control of culturing parameters or their high cost of operation have limited their utility for the production of food products. Instead, large scale cultivation of heterotrophic microalgae using classical fermentation systems provides consistent biomass produced under highly controlled conditions at low cost.
Microalgae contain many of the major lipid classes and fatty acids found in other organisms. However, they are also the principal producers in the biosphere of some polyunsaturated fatty acids, especially docosahexaenoic acid (DHA). The high DHA content found in some algae is currently being utilized to supplement infant formula to enable it to more closely resemble human breast milk. Thus, the commercialization of DHA from microalgae demonstrates the value of these organisms as a source of useful fatty acids. 相似文献
87.
HELEN A. GRUBER PAUL L. KRONICK PETER R. BUECHLER MARY V. HANNIGAN 《Journal of food science》1990,55(6):1506-1509
Collagen, elastin and residual actomyosin in connective tissue of some lower grades of beef were determined from the contents of hydroxy-proline, valine and glutamic acid, using three simultaneous equations based on amounts of these amino acids found in the pure proteins. The complete amino-acid profiles of the connective tissues agreed with the calculated protein compositions. Connective tissues were removed from the meat by dissection, and sequential saline extractions removed sarcoplasmic and myofibrillar proteins. Glycoproteins were removed by extraction with half-saturated calcium hydroxide; collagen, by autoclaving. Changes in composition after extraction or au-toclaving were confirmed by histological investigations. 相似文献
88.
PAUL WHYTE JOHN DANIEL COLLINS KEVINA McGILL CLAIRE MONAHAN 《Journal of Food Safety》2002,22(1):55-65
Commercial immersion chilling systems used in poultry processing are a major source in the cross-contamination of carcasses with pathogenic microorganisms. In the current study, the efficacy of a chlorine based bactericidal compound, sodium dichloroisocyanurate (NADCC), to control contamination between carcasses was compared to the more traditional sodium hypochlorite solutions in a simulated carcass immersion chilling system. The addition of either sodium dichloroisocyanurate or sodium hypochlorite to the immersion chill tank water at concentrations of 50 ppm or more significantly reduced total aerobic mesophilic (37C) and psychrophilic (22C) counts when compared to corresponding untreated water samples in which dressed broiler carcasses had been immersed ( P < 0.01). Both compounds significantly reduced the numbers of fecal coliforms and thermophilic campylobacters in the immersion water samples compared to corresponding control samples ( P < 0.01). In contrast to the control water samples, salmonellae were not detected in immersion water samples treated with either of the chlorine based compounds. 相似文献
89.
INFLUENCE OF GRANULE SIZE ON VISCOSITY OF CORNSTARCH SUSPENSION 总被引:2,自引:0,他引:2
The influence of granule size and size distribution in gelatinized suspensions of 2.6% cornstarch heated at fixed temperatures between 70–90C on the power law viscosity was measured by laser diffraction. In the early stages of gelatinization, where the granule size standard deviation was less than 12 μm, dilatant behavior was observed over the shear rate range 200–1100 S −1 . At constant starch concentration and without granule rupture, suspension consistency, K, increased exponentially with granule mean diameter while the flow behavior index, n, decreased linearly with increase in the extent of gelatinization and the standard deviation of the granule size. The variation of K with granule size and that of n with standard deviation were found to be independent of temperature over 70–90C. In the later stages of gelatinization, where the granules lose their integrity, suspension viscosity progressively decreased as granule rupture continued. 相似文献
90.
A Kinetic Approach to Food Quality Prediction Using Full-History Time-Temperature Indicators 总被引:2,自引:0,他引:2
A mathematical model based on the theory of chemical kinetics was derived to predict food quality change from the response of a full-history time-temperature indicator. A first-order kinetic reaction (n = 1) was used to describe both indicator response and changes in food quality. A storage investigation of mature green tomatoes showed that the quality prediction model satisfactorily predicted changes in tomato firmness induced by variable temperature storage. Tomato firmness as predicted from the response of a LifeLines model 57 time-temperature indicator was not significantly different from the observed changes (F = 1.99, p = 0.18) for 28 days of storage. The mathematical derivation was extended to develop a quality-based interpretation of the shelf life of perishable foods. 相似文献