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61.
Eggs of T. bisselliella were exposed to sub-zero temperatures at a cooling rate of 2°C/h to a minimum of −20°C. Observed mortality was closely approximated by predictions based on an adapted fixed temperature model. The eggs showed no acclimation during cooling. In combination with thermal conductivity models the mortality model provides a simple method to predict exposure times required to reach the desired level of mortality in the cold disinfestation treatment of a commodity or item. With large items, minimum dimension 50 cm, it is predicted that disinfestation will be achieved before the centre has reached −20°C.  相似文献   
62.
The Clean Development Mechanism established under the Kyoto Protocol allows investors in the developed world to invest in the developing world in return for emission credits. The CDM has two goals—to contribute to the reduction of emissions in the developed countries, and to promote sustainable development in the developing country. The objective of this paper is to analyze the project portfolio of 400 published CDM projects in the sector “waste handling and disposal” according to their project and technology characteristics.  相似文献   
63.
This study examined the current governance system for Lake Buhi, Philippines. It describes stakeholder patterns of decision‐making, their roles in the decision‐making process based on their legal mandates, the manner of interactions, the sources of conflict and how these various issues are currently resolved. Stakeholders represent diverse interests, including irrigation, hydropower generation, fishery management and navigation. This study uses data generated from ten key informant interviews of the different stakeholders, information from five round table discussions, and secondary data and reports of various agencies. The results indicate that Lake Buhi and its watershed present classic man‐in‐nature governance challenges. The interplay of internal and external uncertainties regarding multiple uses results in a complex system that is difficult to effectively manage. Climate‐related hazards aggravate the pressures from activities within the lake watershed, complicating water allocation issues. The institutional arrangements that have emerged to address these challenges, however, appear to be fraught with overlaps, fragmentation and a lack of communication. It is thought these deficiencies could be addressed by establishing a lake basin council with representation from all the involved organizations, as well as any stakeholder groups not represented by organizations. The system of governance over the lake must address issues concerning water uses and access to the resource. The capacity of the organizations to participate in such an arrangement is weak, however, and capacity building is needed. The availability and sharing of data and information among stakeholders are also weak and must be strengthened if the work of the lake basin council is to be based on the best available information.  相似文献   
64.
Rubber goods usually require a combination of properties that cannot be provided by one elastomer only and then two or more polymer components have to be mixed to meet specific requirements. In such cases, the additives normally employed in rubber formulations are unevenly distributed, depending on the affinity of each compound to each polymeric phase. Thus, the dispersion of each one of these ingredients in the different rubbers will influence the rate and degree of vulcanization and, in consequence, the performance of the final composite. In this work, natural rubber (NR) and styrene butadiene rubber (SBR) were mixed in a 1 : 1 ratio. The compositions were obtained according to ASTM D 3182, by using four different preparative modes for the incorporation of the additives. After vulcanization, morphological, and dynamic mechanical thermal analysis, tensile strength, hardness, and tear resistance of each composition were investigated. The results show that the best properties were found when the NR/SBR mixture was prepared in such a way as to favor the vulcanization of the SBR phase while preserving the NR phase from excessive vulcanization. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 93: 483–489, 2004  相似文献   
65.
66.
Obtaining pectin through traditional precipitation processes requires a large amount of organic solvent. A reduction in solvent consumption may be achieved by incorporating a cross‐flow microfiltration step in which the extraction solution is removed and pectin is concentrated. In this study, we used α‐alumina tubular membrane (0.44 μm) in two operation modes: total recycle mode to evaluate the effect of temperature, initial concentration of pectin and transmembrane pressure on the permeate flux and pectin coefficient rejection; and batch mode to evaluate the degree of concentration and loss of pectin. It was observed that pectin coefficient rejection varied from 93.4 ± 0.7% to 97.8 ± 0.3%, and a maximum permeate flux of 238.69 ± 6.48 kg m?2 h?1 with 0.12 MPa at 50 °C and 1.0 g kg?1. Using the optimum conditions, the flux observed at the end of the process was 32.8% lower than the flux in the total recycle mode, enabling a final concentration of pectin in the retained solution of 61.04 ± 0.87% with an average pectin loss in the permeate stream of 8.18%.  相似文献   
67.
We report an observational field study that aimed to identify innovative processes in rehabilitant orangutans’ (Pongo pygmaeus) water innovations on Kaja Island, Central Kalimantan, Indonesia. We tested for the basic model of innovating (make small changes to old behavior), 4 contributors (apply old behavior to new ends, accidents, independent working out, social cross-fertilization), development, and social rank. Focal observations of Kaja rehabilitants’ behavior over 20 months yielded 18 probable innovations from among 44 water variants. We identified variants by function and behavioral grain, innovations by prevalence, and innovative processes by relations between innovations, other behaviors, and social encounters. Findings indicate innovating by small changes and some involvement of all 4 contributors; midrank orangutans were the most innovative; and rehabilitants’ adolescent age profile, orphaning, and intense sociality probably enhanced innovativeness. Important complexities include: orangutan innovating may favor certain behavioral levels and narrowly defined similarities, and it may constitute a phase-like process involving a succession of changes and contributors. Discussion focuses on links with great ape cognition and parallels with innovating in humans and other nonhuman species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
68.
This paper describes an incremental converter based on a second order ???? modulator. The scheme uses a 3-bit DAC with inherent linearity, an optimal reset of integrators, and gives rise to an effective offset cancellation with a novel technique based on single or double chopping. The circuit, fabricated in a mixed 0.18-0.6???m CMOS technology, obtains 1.5-??V residual offset with 2VPP fully differential range. The measured resolution is 19 bit obtained with 512 clock periods.  相似文献   
69.
In this study, green synthesis of gold nanoparticles (AuNPs) was performed by a sunlight irradiation method using the Borassus flabellifer fruit extract as a reducing agent. 5‐Fluorouracil (5‐FU)‐loaded GG capped AuNPs (5FU‐G‐AuNPs) was prepared. The nanoparticles was further characterised by UV‐visible spectra, particle size analysis, zeta potential, SAED, HRTEM, and XRD. The MTT assay results showed the suitability 5‐FU‐G‐AuNPs. In this study, 5‐FU‐G‐AuNPs exhibited potential cytotoxic and apoptotic effects on (MiaPaCa‐2) cell line.Inspec keywords: gold, biochemistry, X‐ray diffraction, nanofabrication, biomedical materials, transmission electron microscopy, toxicology, electrokinetic effects, particle size, nanoparticles, cancer, visible spectra, cellular biophysics, ultraviolet spectra, nanomedicine, patient treatment, organic compoundsOther keywords: 5FU‐G‐AuNPs, suitability 5‐FU‐G‐AuNPs, human pancreatic cancer cell, green synthesis, sunlight irradiation method, 5‐Fluorouracil‐loaded GG, in vitro treatment, 5 fluorouracil‐loaded biosynthesised gold nanoparticles, borassus flabellifer fruit extract, reducing agent, UV‐visible spectra, particle size analysis, zeta potential, SAED, HRTEM, XRD, MTT assay, apoptotic effects, cytotoxic effects, MiaPaCa‐2 cell line, Au  相似文献   
70.
The authors of this reply article note that B. Gawronski, E. P. LeBel, K. R. Peters, and R. Banse (see record 2009-05290-002) (a) expressed agreement in their comment with the analysis put forward in the target article (J. De Houwer, S. Teige-Mocigemba, A. Spruyt, & A. Moors) (see record 2009-05290-001) and (b) pointed to a further implication for the way in which the implicitness of a measure should be examined. The current authors note that B. A. Nosek and A. G. Greenwald (see record 2009-05290-003), on the other hand, raised questions in their comment about the definition of the concept “implicit” in the target article, arguing for a fundamentally different approach to measurement that emphasizes not theoretical understanding but usefulness for predicting behavior. In this reply, the current authors respond to these comments and argue that when theoretical claims are made about measures, these claims should be backed up with appropriate evidence. In the absence of basic research, measures and their relation to behavior can only be described. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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