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1.
California is the leading state for the production of almonds, with more than 400,000 bearing hectares of orchards that produced approximately 1 billion kilograms of shelled nuts in 2017. Almond hulls (AH) are a regional by-product feedstuff fed predominantly to dairy cattle in California. A 2012 study surveyed 40 dairy farms in California and found that 39 out of 104 total mixed rations contained AH, with a mean daily feeding rate of 1.45 kg/cow. In 2017, approximately 2 billion kilograms of AH was produced. At a feeding rate of 1.45 kg/cow daily, even if all 1.7 million lactating cows in California are consuming AH, there will be a surplus of AH on the market as the approximately 130,000 nonbearing hectares come into nut production. Therefore, the potential of feeding varying amounts of AH to lactating dairy cows was investigated using 12 Holstein cows with 4 primiparous and 8 multiparous cows. The dietary treatments were 4 total mixed rations containing 0, 7, 13, or 20% AH. The AH used contained 12.8% crude fiber (as-is basis), which was below the 15% legal limit set by state feed regulations. Diets were formulated so that as the inclusion rate of AH increased, the amount of steam-flaked corn and soyhull pellets decreased and soybean meal inclusion increased. Experimental design was a replicated 4 × 4 Latin square. Diet had a cubic effect on actual milk yield, energy-corrected milk yield, and dry matter intake, with the 7% AH diet having the highest values and the 13% AH diet having the lowest. The percent and yield of total solids and the yields of lactose and fat did not differ with diet, but percent and yield of protein declined linearly with increased AH inclusion, and fat percent increased linearly. Apparent total-tract digestibilities of dry matter and organic matter were higher with the inclusion of AH in the diet. Total percentage of the day spent ruminating increased linearly with higher amounts of AH. Overall, this work demonstrated that AH can be fed at varying amounts, up to 20% of the diet, to lactating dairy cows to support high levels of milk production and that increasing amounts of AH (up to 20%) in the diet could lead to improved digestibility and milk fat percentage but decreased milk protein production.  相似文献   
2.
This research studied the effect of fused deposition modeling (FDM) 3D printing on three phase dielectric nanocomposites using poly(vinylidene) fluoride (PVDF), BaTiO3 (BT), and multiwall carbon nanotubes (CNTs). PVDF polymer and BT ceramics are piezo-, pyro- and di-electric materials extensively used for sensor and energy storage/harvesting applications due to their unique characteristic of dipole polarization. To increase dielectric property, CNTs have been recently utilized for uniform dispersion of BT nanoparticles, ultrahigh polarization density, and local micro-capacitor among matrix. It was proved that 3D printing process provides homogeneous dispersion of nanoparticles, alleviating agglomeration of nanoparticles and reducing micro-crack/voids in matrix which can potentially enhance their dielectric property than traditional methods. In this research, these three-phase nanocomposites are fabricated through FDM 3D printing process and characterized for dielectric property. Increasing both BT and CNT nanoparticles improves dielectric properties, while CNTs have a percolation threshold near 1.7?wt%. The most desirable combination of dielectric constant and loss properties (118 and 0.11 at 1?kHz) is achieved with nanocomposites containing 1.7?wt%-CNT/45?wt%-BT/PVDF. These results provide not only a technique to 3D print dielectric nanocomposites with improved dielectric property but also large-scale electronic device manufacturing possibility with freedom of design, low cost, and faster process.  相似文献   
3.
Fine-spray (water mist) protection of shipboard engine rooms   总被引:1,自引:0,他引:1  
Twenty-three fire tests were conducted to determine the ability of current fine-spray (water mist) technologies to extinguish fires specified in the International Maritime Organization (IMO) fire test procedure for engine rooms greater than 3000 m3. The tests were conducted using nozzle installed at a 5 m height and 1·5 m spacing in a large test facility (2800 m2 area and 18 m height). Two types of nozzles were tested: a low pressure nozzle operating between 1·2 and 1·5 MPa with flow per nozzle between 12·0 and 13·41/m and a multi-nozzle high-pressure prototype consisting of seven nozzles operating at 6·9 MPa flowing at 5·3 1/m per prototype. These nozzles were selected because they had been shown to extinguish IMO fire tests in enclosures with a protected area of 83 m2 and a ceiling height of 4·5 m. The fire tests selected from the IMO procedure included 6 MW diesel spray fires on top of the IMO engine mock-up, a shielded 6 MW diesel spray fire adjacent to the mock-up, a 1 MW shielded diesel spray fire adjacent to the mock-up, and a wood crib within a 2 m2 pan filled with heptane. In tests in which no additional enclosure surrounded the nozzles other than the test facility, fires were not significantly affected by the water mist using either nozzle. To further investigate mist-system capabilities, a ceiling was then placed directly over the nozzles at a 5 m height covering an area of 188 m2. Using 90 high-pressure prototype nozzles, the test fires were not extinguished. A 940 m3 enclosure was then formed by dropping tarpaulins to the floor from the ceiling. A 4 m2 vent was placed in the wall. With the 90 high-pressure prototype nozzles, the 6 MW spray fire on top of the mock-up was extinguished. When the 6 MW fire was shielded beside the mock-up, the fire was not extinguished. With the vent closed, the 6 MW shielded spray fire was extinguished. Under the same test conditions, a 1 MW shielded diesel spray fire and a 0·1 m2 heptane pool fire were not extinguished. The fire test results indicated that protection of engine rooms with volumes of about 1000 m3 is possible by optimizing current fine-spray technology while significantly larger volumes will require improved discharge characteristics.  相似文献   
4.
Fire tests were conducted using the Underwriters Laboratories (UL) UL 1626 Fire Test for residential sprinklers. The results indicated that sprinkler performance in UL 1626 could not be reproduced due to differences in material flammability properties. This conclusion was reached in a cooperative effort with UL. Factory Mutual Research's Approval fire test that had been redesigned based on UL 1626 was thus subject to the same variability. A new fire test was developed using fuel with controlled material flammability parameters based upon the use of the ASTM E2058 Fire Propagation Apparatus. The new fuel package consists of a wood crib (one half the height of the one which was used in UL 1626) supported over a pan with heptane, two polyether foam cushions (about 60% greater in density than the foam previously used in UL 1626) measuring 34 in by 30 in by 3 in (864 mm by 762 mm by 76 mm) and in (6 mm) Douglas Fir plywood paneling. The new fire test was shown in a series of sprinklered fire tests to provide a reproducible challenge to residential sprinklers comparable to that observed in the Factory Mutual Research and the Los Angeles Residential Test Programs.  相似文献   
5.
The theme of a more compact city has been a central feature of planning policy for Sydney's development over the last two decades. Urban consolidation, in the form of attached dwellings in medium- and high-density configurations, has become the predominant form of new residential development since the early 1990s. One of the largely untested claims for this policy is that it provides more housing choice for an increasingly diverse population and that simply building larger amounts of smaller housing in high-density concentrations will be sufficient to meet that demand. As a result, planning for higher density housing has been undertaken with little explicit recognition of the housing sub-markets higher density housing caters for or their specific spatial characteristics within the city. These issues are examined by an analysis of the socio-economic characteristics of areas with high concentrations of attached housing. These data are processed by factor analysis to identify and locate the range of sub-markets within attached housing and additional small area data used to fill out the market profiling. The results reveal that a range of specific housing needs are met by this form of housing with discriminative characteristics in certain locations. In other words, higher density housing is associated with a range of locationally specific and spatially distinctive sub-markets. These findings are particularly relevant and timely as a new metropolitan strategy is in preparation for Sydney where an estimated 60–70 per cent of new dwelling provision in the next 30 years will take place within existing suburbs through higher density redevelopment. Planning for such development must take into account the local markets for such accommodation which have very different characteristics in different parts of the city.  相似文献   
6.
Large open-ended pipe pile has been found to be advantageous for use in transportation projects. The current design method, however, is not adequately developed. To close this practice gap, this paper first summarized different design methods for open-ended pipe piles in sandy soils. A major factor for all the design codes is to properly account for the formation and effects of soil plug. The comparison indicates that there is a large variation in the base capacity evaluation among different methods due to the complex behaviors of soil plug. To close the knowledge gap, discrete element method (DEM) was used to simulate the soil plugging process and provide insight on the plugging mechanism. The simulation results show that the arching effect significantly increases the internal unit shear resistance along pipe piles. The porosity distribution and particle contact force distribution from DEM model indicate a large stress concentration occurs at the bottom of the soil plug. Besides, nearly 90% of the plug resistance is provided by the bottom half portion of the soil column. The soil-pile friction coefficient has a significant effect on the magnitude of plug resistance, with the major transition occurred for friction coefficient between 0.3 and 0.4.  相似文献   
7.
After earlier promising results for the control of anthracnose in avocado fruit by thyme vapours, our studies were extended to commercial use in tray packs. The effect of thyme oil low-density polyethylene impregnated pellets (TO-LDPE-P) in polylactic acid (PLA) sachets was investigated for the control of anthracnose and retention of dietary phytochemicals, fatty acid composition, D-mannoheptulose sugar and fruit quality in ready-to-eat avocado fruit. The 10% TO-LDPE-P significantly reduced the incidence severity of anthracnose and enabled the retention of dietary phytochemicals (p-coumaric, ferulic and caffeic acid, catechin and epicatechin), fatty acids, mannoheptulose, fruit firmness and taste compared to the currently used prochloraz® fungicide treatment. The results of this study strongly suggest the incorporation of 10% TO-LDPE-P in PLA sachets in commercial avocado tray packs as a natural option to improve fruit health, dietary phytochemicals, fatty acid composition and consumer satisfaction.  相似文献   
8.
A new approach to the creation of design tools is proposed that addresses the real information needs of designers in the early stages of design of non-residential buildings. Traditional simplified design tools are typically too limited to be of much use, even in conceptual design. The proposal is to provide access to the power of detailed simulation tools at a stage in design when little is known about the final building, but at a stage also when the freedom to explore options is greatest and the ability to improve the design is greatest. The concept of the building performance sketch forms the basis of the proposed design tool. It was derived from consultation with design analysis teams as part of the development of the COMFEN tool for fenestration design. Tools like COMFEN are explored to understand how they were shaped by consultation and how requests from these teams for real-world relevance might shape such tools in the future. The simulation process can effectively utilize some of the as-built, as-occupied and as-managed lessons on behaviours and technical outcomes from the Post-occupancy Evaluation (PoE) of buildings.

Il est proposé pour la création des outils de conception une nouvelle approche répondant aux véritables besoins d'information des concepteurs dans les premières phases de conception des bâtiments non résidentiels. Les outils de conception simplifiée traditionnels sont habituellement trop limités pour être très utiles, même en design conceptuel. Ce qui est proposé est de pouvoir accéder à la puissance d'outils de simulation détaillée à un stade de la conception où l'on sait encore peu de choses concernant le bâtiment final, mais également à un stade auquel la liberté d'exploration des options possibles comme la capacité d'amélioration de la conception sont les plus grandes. Le concept du schéma de performance du bâtiment constitue la base de l'outil de conception proposé. Il découle de la consultation des équipes chargées de l'analyse de la conception dans le cadre du développement de l'outil COMFEN de conception du fenêtrage. Des outils tels que COMFEN sont examinés afin de comprendre comment ils ont été modelés par la consultation et comment les demandes de ces équipes en termes de pertinence réelle pourraient façonner ces outils à l'avenir. Le processus de simulation peut tirer efficacement parti de certaines des leçons, conformes à l'exécution, à l'occupation et à la gestion, en matière de comportements et de résultats techniques, retirées de l'Evaluation Après Occupation des bâtiments.

modèles d'information du bâtiment?bâtiments?processus de conception?outils de conception?début de conception?efficacité énergétique?retour d'information?simulation des performances?évaluation après occupation  相似文献   
9.
This article identifies issues around the Auckland Region's strategy for urban intensification and discusses the ensuing policy implications. Medium density housing forms an important element of the strategy for growth management. Implications for its success are primarily drawn from research into a major housing development in Waitakere City. It is argued that for ideological, political and technical reasons the strategy could be easily undermined. The article also suggests that something of a paradigm shift is underway in urban planning.  相似文献   
10.
NEO河畔公寓     
在这个严谨而杰出作品中,细部和建造技术格外受关注。建筑中每样东西都是美的创造。It's a tour de force of rigour,exceptional attention to detail,and engineering,Everything is beautifully made.这个住宅项目位于伦敦河畔地区的核心地带,它靠近泰晤士河,并与泰特现代艺术馆扩建部分的西门直接相对,NEO河畔公寓包括217个居住单元,分布于四栋建筑的12层至24层间。这四个六边形的大楼给居住者提供了舒适的居住条件、良好的景观视野和充足的阳光。这些钢和玻璃建造的塔楼,与周边环境形成了呼应。  相似文献   
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