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1.
Titanium dioxide (TiO2) nanostructures (nanorods and nanoparticles) were prepared using a low-cost microwave irradiation method from a polyol medium of glycerol. Titanium glycerolate and TiO2 powders were obtained in the glycerol medium for the first time with four different power densities (240?W, 480?W, 720?W, 960?W) of irradiation using a domestic microwave oven of 2.45?GHz, to understand the impact of power on morphology tuning. The structural and morphological features of the titanium glycerolate and TiO2 powders were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and Raman spectra analysis. The TiO2 was successfully used in the fabrication of photovoltaic devices and as a proof-of-concept binder free paste was prepared and successfully employed for photo-anode using screen printing on the fluorine-doped tin oxide substrate.  相似文献   
2.
Although predictive machine learning for supply chain data analytics has recently been reported as a significant area of investigation due to the rising popularity of the AI paradigm in industry, there is a distinct lack of case studies that showcase its application from a practical point of view. In this paper, we discuss the application of data analytics in predicting first tier supply chain disruptions using historical data available to an Original Equipment Manufacturer (OEM). Our methodology includes three phases: First, an exploratory phase is conducted to select and engineer potential features that can act as useful predictors of disruptions. This is followed by the development of a performance metric in alignment with the specific goals of the case study to rate successful methods. Third, an experimental design is created to systematically analyse the success rate of different algorithms, algorithmic parameters, on the selected feature space. Our results indicate that adding engineered features in the data, namely agility, outperforms other experiments leading to the final algorithm that can predict late orders with 80% accuracy. An additional contribution is the novel application of machine learning in predicting supply disruptions. Through the discussion and the development of the case study we hope to shed light on the development and application of data analytics techniques in the analysis of supply chain data. We conclude by highlighting the importance of domain knowledge for successfully engineering features.  相似文献   
3.
Journal of Materials Science - For transformers and inductors to meet the world’s growing demand for electrical power, more efficient soft magnetic materials with high saturation magnetic...  相似文献   
4.
The primary driver for a successful biological nutrient removal is the availability of suitable carbon source, mainly in the form of volatile fatty acids (VFA). Several methods have been examined to increase the amount of VFAs in wastewater. This study investigates the mechanism of mechanical disintegration of thickened surplus activated sludge by a deflaker technology for the production of organic matter. This equipment was able to increase the soluble carbon in terms of VFA and soluble chemical oxygen demand (SCOD) with the maximum concentration to be around 850 and 6530 mgl(-1), for VFA and SCOD, respectively. The particle size was reduced from 65.5 to 9.3 microm after 15 min of disintegration with the simultaneous release of proteins (1550 mgl(-1)) and carbohydrates (307 mgl(-1)) indicating floc disruption and breakage. High performance size exclusion chromatography investigated the disintegrated sludge and confirmed that the deflaker was able to destroy the flocs releasing polymeric substances that are typically found outside of cells. When long disintegration times were applied (>or=10 min or >or=9000 kJkg(-1)TS of specific energy) smaller molecular size materials were released to the liquid phase, which are considered to be found inside the cells indicating cell lysis.  相似文献   
5.
There is extensive research on the negative health impacts of poor housing quality. However, little is known about the potential health benefits of high-quality housing in poor neighbourhoods. Neighbourhoods with unexpectedly good health outcomes despite high levels of deprivation have been deemed resilient places and housing quality in these areas may be a contributor to this resilience. This study aimed to evaluate whether an indicator of neighbourhood housing quality was associated with a previously quantified resilience index (RINZ) in New Zealand. It was found that areas with high housing quality tended to have higher median income, greater proportions of partnered people and shorter-term residents, and very low proportions of Māori. A positive association was found between housing quality and resilience, after adjustment for deprivation. There was no indication of differences by heterogeneity in housing quality within the aggregate unit of analysis. These findings pose the hypothesis that improving housing quality in similarly deprived areas that have poor health outcomes could potentially boost health. To extend this understanding, further development of a more sophisticated housing quality indicator is recommended.  相似文献   
6.
Conference news     
RESOURCES: ENVIRONMENT AND POLICY, by John Fernie and Alan Pitkethly, Harper and Row, London, 1985, 338 pp. (#bp12.95, paperback)

THE ECONOMICS OF FORESTRY AND NATURAL RESOURCES, by Per‐Olov Johansson and Karl‐Gustaf Lofgren, Basil Blackwell, Oxford, 1985, 292 pp. (#bp29.50, hardback only)

ENVIRONMENTAL PROTECTION: STANDARDS, COMPLIANCE AND COSTS, edited by T. J. Lack, J. Wiley &; Son, Chichester, 1984, 329 pp. (#bp30, hardback)

ENVIRONMENT AND ENFORCEMENT: REGULATION AND THE SOCIAL DEFINITION OF POLLUTION, by K. Hawkins, Clarendon Press, Oxford, 1984, 253 pp. (#bp15 hardback; #bp6.95, paperback)

ENVIRONMENTAL POLICY, VOLUME 1: ELEMENTS OF ENVIRONMENTAL ANALYSIS, by George Tolley, Philip Graves and Glenn Blomquist, Ballinger, Cambridge, Mass, and Harper and Row, London, 1981. (#bp27.50, hardback)

ENVIRONMENTAL POLICY, VOLUME 4: SOLID WASTES, by George Tolley, Jospeh Havlicek and Robert Fabian, Ballinger, Cambridge, Mass. and Harper and Row, London, 1985. (#bp44.00, hardback)

World Health Organisation, ENVIRONMENTAL POLLUTION CONTROL IN RELATION TO DEVELOPMENT, World Health Organisation, Geneva, Technical Report Series, 718, 1985, 63 pp.

TRANSPORT IS FOR PEOPLE: NINTH INTERNATIONAL SYMPOSIUM ON THEORY AND PRACTICE IN TRANSPORT ECONOMICS, European Conference of Ministers of Transport, 1983, Paris (#bp15.00)

RECREATION MANAGEMENT AND PRICING, by A. G. Bovaird, M. J. Tricker and R. Stoakes, Gower Press, Aldershot, 1984, 182 pp. (#bp15, hardback)

URBAN LAND AND SHELTER FOR THE POOR, by Patrick McAuslan, Earthscan#shInternational Institute for Environment and Development, London, 1985, 145 pp.

CARING FOR THE UNEMPLOYED. Prepared for the Association of Metro‐polital Authorities by Susan Balloch, Chris Hume, Brian Jones and Peter Westland. Publishers: Bedford Square Press, London, 1985, for the National Council for Voluntary Organisations.

THE LONG‐TERM UNEMPLOYED. ACTION FOR A FORGOTTEN MILLION, by Peter Ashby (Head, NVCO Policy Analysis Unit). An NCVO Policy Discussion document, Bedford Square Press, London (1985).

ANTHROPOGENIC COMPOUNDS: Volume 3 Part C of The Handbook of Environmental Chemistry, edited by O. Hutzinger, Springer‐Verlag, Germany, 248 pp. 1986. (DM 188.00)

HEAVY METALS IN NATURAL WATERS: APPLIED MONITORING AND IMPACT ASSESSMENT, by James W. Moore and S. Ramamoorthy, Springer‐Verlag, U.S.A. and Germany, viii #pl 268 pages, index, 1984. (DM 108.00)

DESTRUCTION AND DISPOSAL OF PCBs BY THERMAL AND NON‐THERMAL METHODS, by D. G. Ackerman, L. L. Scinto, P. S. Bakshi, R. G. Delumyea, R. J. Johnson, G. Richard, A. M. Takata and E. M. Sworzyn. Noyes Data Corporation, Park Ridge, New Jersey, 1983, xiv #pl 417 pages (no index). (#dl48.00)

ELECTROSTATIC PRECIPITATOR MANUAL (Pollution Technology Review No. 91), by Jack R. McDonald and Alan H. Dean, Noyes Data Corporation, U.S.A., 1982. (#dl48.00)

PATTY'S INDUSTRIAL HYGIENE AND TOXICOLOGY, edited by Lewis J. Cralley and Lester V. Cralley, Volume 3 (2nd Edition)—Theory and Rationale of Industrial Hygiene Practice: (i) Volume 3A—The Work Environment (#bp97.20); (ii) Volume 3B—Biological Responses (#bp92.00) J. Wiley and Sons Ltd., Chichester U.K. 1985.

SAFE DRINKING WATER. THE IMPACT OF CHEMICALS ON A LIMITED RESOURCE, edited by R. G. Rice, J. Wiley and Sons, Chichester, U.K., Lewis Publishers Inc. Chelsea MI, 1985. (#bp36.00)

PLANTS FOR ARID LANDS. (Proceedings of the Kew International Conference on Economic Plants for Arid Lands held in the Jodrell Laboratory, Royal Botanic Gardens, Kew, England, 23‐27 July 1984), edited by G. E. Wickens, J. R. Goodwin and D. V. Field. George Allen and Unwin, London, 1985. (#bp30.00)

REGULATED RIVERS, edited by A. Lillehammer and S. J. Saltveit, Univer‐sitetsforlaget AS, Oslo, 1984. (#bp47.50)

NUTRIENT CYCLING IN TROPICAL FOREST ECOSYSTEMS, by C. F. Jordan, Wiley, Chichester, 1985. (#bp13.45)  相似文献   
7.
This paper addresses the ability of five low-cost reactive materials to remove Zn, Pb, and Cd from Fe-poor, circum-neutral pH metal mine water in Mid-Wales, UK. Compost, fly ash, waste shell material, iron ochre, and a mixture of blast furnace slag (BFS) and basic oxygen furnace slag (BOS) were used in a series of small-scale passive treatment cells to assess metal removal from mine drainage initially containing, on average, 23.5 mg/L Zn, 0.5 mg/L Pb, and 0.05 mg/L Cd. Trial treatment cells contained between 1.5 and 12 kg of reactive media, had a 15 min residence time, and treated a discharge of up to 1 L per minute. Fly ash from a peat-fired power station was found to be the most effective material for metal removal, with concentrations reduced to 0.02 mg/L Zn, 0.0069 mg/L Pb, and 0.0001 mg/L Cd from over 1,000 L of water (between 98.6 and 99.9% removal). The other materials initially achieved high levels of metal removal (between 75 and 99.9% Zn, Pb, and Cd removed); however, all of the materials were saturated with Zn after less than 200 L of water had been treated. Metal sorption ranged from 21.4 mg/g Zn for the peat fly ash to 0.0015 mg/g Cd for the compost and BOS/BFS slag. The results of the pilot-scale field trials can be scaled to demonstrate that a modest-sized fly ash treatment cell (2.6 × 2.6 × 1 m) in size would be sufficient to remove 90% of the total metal load (Pb, Zn, and Cd) from this 10 L/min mine water discharge for a 1 year period. Importantly this research demonstrates that passive treatment for metal mine drainage can comply with water quality directives but cannot be considered a ‘walk-away’ solution; it requires modest (potentially annual) maintenance.  相似文献   
8.
The microstructures, hardness and corrosion behavior of high chromium cast irons with 20, 27 and 36 wt.%Cr have been compared. The matrix in as-cast 20 wt.%Cr, 27 wt.%Cr and 36 wt.%Cr high chromium cast irons is pearlite, austenite and ferrite, respectively. The eutectic carbide in all cases is M7C3 with stoichiometry as (Cr3.37, Fe3.63)C3, (Cr4.75, Fe2.25)C3 and (Cr5.55, Fe1.45)C3, respectively. After destabilization at 1000 °C for 4 h followed by forced air cooling, the microstructure of heat-treatable 20 wt.%Cr and 27 wt.%Cr high chromium cast irons consisted of precipitated secondary carbides within a martensite matrix, with the eutectic carbides remaining unchanged. The type of the secondary carbide is M7C3 in 20 wt.%Cr iron, whereas both M23C6 and M7C3 secondary carbides are present in the 27 wt.%Cr high chromium cast iron. The size and volume fraction of the secondary carbides in 20 wt.%Cr high chromium cast iron were higher than for 27 wt.%Cr high chromium cast iron. The hardness of heat-treated 20 wt.%Cr high chromium cast iron was higher than that of heat-treated 27 wt.%Cr high chromium cast iron. Anodic polarisation tests showed that a passive film can form faster in the 27 wt.%Cr high chromium cast iron than in the 20 wt.%Cr high chromium cast iron, and the ferritic matrix in 36 wt.%Cr high chromium cast iron was the most corrosion resistant in that it exhibited a wider passive range and lower current density than the pearlitic or austenitic/martensitic matrices in 20 wt.%Cr and 27 wt.%Cr high chromium cast irons. For both the 20 wt.%Cr and the 27 wt.%Cr high chromium cast irons, destabilization heat treatment gave a slight improvement in corrosion resistance.  相似文献   
9.
Thermocouples can be calibrated at pure metal ingot-based fixed points at temperatures up to the freezing point of copper (1084.62 °C). For Pt/Pd thermocouples, the deviation from the accepted reference function very often takes an approximately linear form up to the copper fixed point. The calibration of Pt/Pd thermocouples may therefore be more amenable to extrapolation than that of Pt/Pt-Rh thermocouples. Here, the melting temperatures of a Co?CC and a Pd?CC eutectic fixed point are determined by extrapolating the deviation functions of several Pt/Pd thermocouples, after the fashion of Edler et al. The results are compared with the melting temperatures measured using non-contact radiation thermometry. The expanded uncertainty (k = 2) of the melting temperatures determined by extrapolation of the Pt/Pd thermocouple calibrations is ±0.32 °C for the Co?CC fixed point, and ±0.49 °C for the Pd?CC fixed point. For both fixed points, these uncertainties are comparable to those of non-contact radiation thermometry measurements. While a number of assumptions are made in performing the extrapolation of the calibrations, the method does appear to offer a useful complement to non-contact radiation thermometry measurements.  相似文献   
10.
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