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101.
Gerard E. O’Connor Jeffrey Evans Scott Black Neil Fettell Beverley Orchard Ron Theo 《Nutrient Cycling in Agroecosystems》2010,86(2):269-286
Nitrate is known to accumulate under legume crops. The effects of legume crop, inoculation, row width, sowing rate, sowing
date, and intra-cropping with wheat, on the amount and soil distribution of mineral N, residual soil water, crop biomass and
crop N were studied at Wagga Wagga in south-east Australia. After removal of most of the above-ground plant material, the
treatment effects on the biomass, N content, grain yield and grain N of wheat, established in the following season, were also
measured. In a later experiment at Wagga, the recovery of 15N applied to the mid-row of lupin crops established at three row
widths was estimated at crop maturity. At Condobolin, row width effects on the soil distribution of mineral N, biomass, N
accumulation and N fixation of crop legumes and cereals, were determined. At physiological maturity, at Wagga Wagga, very
little nitrate was left beneath cereals. Significantly more was left under legume crops, mostly below 30 cm of soil depth,
and it was distributed differently depending on crop, inoculation, and sampling location. More nitrate was left under pea
and faba than under lupin, and in response to inoculation. Mixing wheat with narrow-leaf lupin did not prevent nitrate accumulation
in soil. For most of the legumes more nitrate was left in the mid-row than in the in-row; and more nitrate was left at the
mid-row of lupin crops sown with wider rows. The additional nitrate left with wider rows increased the growth, N content,
grain yield and protein of wheat established in the following season. 15N labelled nitrate applied mid-row was used less effectively
by lupin as row width increased, in a dry season. At Condobolin, lupin established with wide rows used less soil nitrate than
with narrower rows but maintained crop N by increased N fixation. In contrast, field pea maintained N demand by increasing
nitrate uptake at intermediate row spacing. The study shows that the amount of nitrate accumulated in soil during legume cropping
is susceptible to agronomic management, particularly crop selection, row width and inoculation; and that variation in the
amount of this nitrate may carry forward to impact wheat production in the follow-on season. 相似文献
102.
An adaptive approach to control a water valve for a cooling coil, called an adaptive fuzzy logic controller (AFLC), is developed and validated in this study. The AFLC calculates the error between the supply air temperature and the supply air temperature set point for air in an air handling unit (AHU) of a heating, ventilating, and air conditioning (HVAC) system and continues to improve the fuzzy controller parameters to minimize the error. The AFLC uses genetic algorithms (GAs) to improve the fuzzy rule matrix and fuzzy membership functions for the AHU in HVAC systems. In this paper, the application of genetic algorithms for developing the AFLC is presented. After a brief background on fuzzy logic controllers and GA theory, the use of GAs is explained. Three methods of modifying the fuzzy rule matrix using the GAs are presented along with simulation and real-time experimental results. Experimental results indicate that GAs can be successfully applied to modify an AFLC rule matrix to achieve a better controller. 相似文献
103.
Ron Zevenhoven Anders Wiklund Johan Fagerlund Sanni Eloneva Ben In’t Veen Hans Geerlings Gert Van Mossel Harold Boerrigter 《Frontiers of Chemical Engineering in China》2010,4(2):110-119
The use of carbon dioxide (CO2) and calcium-containing by-products from industrial activities is receiving increasing interest as a route to valuable carbonate
materials while reducing CO2 emissions and saving natural resources. In this work, wet-chemical experimental data was assessed, which involved the carbonation
of three types of materials in aqueous solutions, namely, 1) wollastonite, a calcium silicate mineral, 2) steelmaking slag,
a by-product of steel production, and 3) paper bottom ash (PBA) from waste paper incineration. Aims were to achieve either
a high carbonation degree and/or a pure carbonate product with potential commercial value. Producing a pure precipitated calcium
carbonate (PCC) material that may find use in paper industry products puts strong requirements on purity and brightness. The
parameters investigated were particle size, CO2 pressure, temperature, solid/liquid ratio, and the use of additives that affect the solubilities of CO2 and/or calcium carbonate. Temperatures and pressures were varied up to 180°C and 4 MPa. Data obtained with the wollastinite
mineral allowed for a comparison between natural resources and the industrial by-product materials, the latter typically being
more reactive. With respect to temperature and pressure trends reported by others were largely confirmed, with temperatures
above 150°C introducing thermodynamic limitations depending on CO2 pressure. The influence of additives showed some promise, although costs may make recycling and reuse of additives a necessity
for a large-scale process. When using steelmaking slag, magnetic separation may remove some iron-containing material from
the process (although this is far from perfect), while the addition of bicarbonate supported the removal of phosphorous, aside
from improving calcium extraction. The experiments with paper bottom ash (PBA) gave new data, showing that its reactivity
resembles that of steelmaking slag, while its composition results in relatively pure carbonate product. Also, with PBA no
additives were needed to achieve this. 相似文献
104.
A small commercially available laboratory mill was found to be suitable to dehull small batches of sorghum grain. The device used one grinding plate and an agitating dimpled plate and took about 1 min to adequately dehull the grain. At the completion of dehulling period decorticated grain was collected directly in a sample holder. Data from various cultivars, grain sizes and types of grain were reproducible. It only required 10 s to clear the device between samples. 相似文献
105.
106.
Jeffrey Perl Sahir Kalim Ron Wald Marc B. Goldstein Andrew T. Yan Nazanin Noori Mercedeh Kiaii Julia Wenger Christopher Chan Ravi I. Thadhani S. Ananth Karumanchi Anders H. Berg 《Hemodialysis international. International Symposium on Home Hemodialysis》2016,20(4):510-521
Introduction Among conventional hemodialysis (CHD) patients, carbamylated serum albumin (C‐Alb) correlates with urea and amino acid deficiencies and is associated with mortality. We postulated that reduction of C‐Alb by intensive HD may correlate with improvements in protein metabolism and cardiac function. Methods One‐year observational study of in‐center nocturnal extended hemodialysis (EHD) patients and CHD control subjects. Thirty‐three patients receiving 4‐hour CHD who converted to 8‐hour EHD were enrolled, along with 20 controls on CHD. Serum C‐Alb, biochemistries, and cardiac MRI parameters were measured before and after 12 months of EHD. Findings EHD was associated with reduction of C‐Alb (average EHD change ?3.20 mmol/mol [95% CI ?4.23, ?2.17] compared to +0.21 [95% CI ?1.11, 1.54] change in CHD controls, P < 0.001). EHD was also associated with increases in average essential amino acids (in standardized units) compared to CHD (+0.38 [0.08, 0.68 95%CI]) vs. ?0.12 [?0.50, 0.27, 95% CI], P = 0.047). Subjects who reduced C‐Alb more than 25% were found to have reduced left ventricular mass, increased urea reduction ratio, and increased serum albumin compared to nonresponders, and % change in C‐Alb significantly correlated with % change in left ventricular mass. Discussion EHD was associated with reduction of C‐Alb as compared to CHD, and reduction of C‐Alb by EHD correlates with reduction of urea. Additional studies are needed to test whether reduction of C‐Alb by EHD also correlates with improved clinical outcomes. 相似文献
107.
Ron Craig 《Construction Management & Economics》2013,31(1):91-100
The UK's NJCC Code of Procedure for Single Stage Selective Tendering (now withdrawn) and its successor, the CIB's Code of Practice for the Selection of Main Contractors are criticized in the light of decisions of the common law courts with regard to regulation of the tendering process. It is argued that a new ‘Tendering Code’ should be produced in the style and format of a contract document which reflects not only the statutory regulation imposed on public bodies, but common law decisions of the courts. The nature of this tendering contract is explained as a means of regulating the tendering process. Issues discussed are: dealing with errors and irregularities found in tenders; dealing with non-compliant tenders; dealing with tender withdrawal prior to its acceptance or rejection; making provisions as to time for submission of tenders and dealing with late tenders; making provision for submission of tender by fax or other electronic means; making provision for evaluation of tenders received; and imposing or negotiating reductions in price with tenderers prior to acceptance. The paper concludes that the common law obligations placed on the owner to treat all tenderers equally and fairly and to apply the tender conditions when evaluating tenders and awarding contracts seems to be good common sense and of commercial advantage, not only to the immediate parties concerned but also to the wider community. 相似文献
108.
Ron Wilson 《电子设计技术》2006,13(8):50-58
从消费电子市场最容易得到的经验是集成为王。移动型战胜便携型,掌上型战胜移动型,而衬衫口袋型又超过掌上型。即使像游戏机这类桌面设备,时髦的外形和低制造成本目标也要靠更高集成度才能实现。这一趋势并不限于低成本的消费电子产品。军用、汽 相似文献
109.
This bench-scale study investigated the passage of particle-associated bacteriophage through a dual-media (anthracite-sand) filter over a complete filter cycle and the effect on subsequent ultraviolet (UV) disinfection. Two model viruses, bacteriophages MS2 and T4, were considered. The water matrix was de-chlorinated tap water with either kaolin or Aldrich humic acid (AHA) added and coagulated with alum to form floc before filtration. The turbidity of the influent flocculated water was 6.4+/-1.5 NTU. Influent and filter effluent turbidity and particle counts were measured as well as headloss across the filter media. Filter effluent samples were collected for phage enumeration during three filter cycle stages: (i) filter ripening; (ii) stable operation; and (iii) end of filter cycle. Stable filter operation was defined according to a filter effluent turbidity goal of <0.3 NTU. Influent and filter effluent samples were subsequently exposed to UV light (254 nm) at 40 mJ/cm(2) using a low pressure UV collimated beam. The study found statistically significant differences (alpha=0.05) in the quantity of particle-associated phage present in the filter effluent during the three stages of filtration. There was reduced UV disinfection efficiency due to the presence of particle-associated phage in the filter effluent in trials with bacteriophage MS2 and humic acid floc. Unfiltered influent water samples also resulted in reduced UV inactivation of phage relative to particle-free control conditions for both phages. Trends in filter effluent turbidity corresponded with breakthrough of particle-associated phage in the filter effluent. The results therefore suggest that maintenance of optimum filtration conditions upstream of UV disinfection is a critical barrier to particle-associated viruses. 相似文献
110.