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1.
The Munich Community Health Service (Medical School-Service Department) conducted an alcohol prevention project in ten public secondary schools. The 423 pupils (11-17 years of age) filled in a questionnaire on alcohol and discussed it afterwards under the guidance of a school physician and a teacher using guideline information. The results of the survey are presented in this paper. Additionally, suggestions for transferring the results to conceptualize and carry out preventive measures are made. The results indicate that the first experience with alcohol occurred early in life. One-fifth of the sample had already tried alcohol at the age of six. Immediate effects of alcohol (e.g. state of drunkenness) were experienced by 35.7 percent of the sample group. Kiosks, shops, and beverage stores were named most frequently as sources for alcohol. The sources of social support varied with respect to sex and age. With increasing age of the children, parents were contacted less frequently whereas the role of peers increased. The present results supply possible paths of action for the development of successful prevention strategies, e.g. by pointing out the early age of onset as well as specific sources of alcohol acquisition.  相似文献   
2.
In this study, we focused on the synthesis, characterization, and adsorption capacity testing of aminated glycidyl methacrylate grafted rice husk (RH‐g‐GMA–Am). Our goal was to obtain a high‐performance surface for the adsorption of various anions. Glycidyl methacrylate grafted rice husk (RH‐g‐GMA) was prepared by the graft copolymerization of glycidyl methacrylate with rice husk; the product was further subjected to an amination reaction. The surface properties, sorption characteristic functional groups, isotherm and kinetic studies, pore diffusion models, and effects of the temperature and pH on the material properties were studied under batch conditions. The IR spectroscopy results show additional surface functional groups for RH‐g‐GMA–Am. The adsorptions of and on RH‐g‐GMA–Am were found to follow pseudo‐second‐order kinetics; this indicated a possible dominant role played by chemisorption. The rate‐limiting step for mass transfer was found to be boundary layer diffusion. Furthermore, the sorption isotherms for and fit the Langmuir model. The amination of RH‐g‐GMA drastically increased the removal efficiency from 3 to 82% and from 6 to 93% for and , respectively. Moreover, RH‐g‐GMA–Am exhibited a better removal efficiency in the pH range of 4–6.5. Regeneration studies revealed that the surface of RH‐g‐GMA–Am could be regenerated repetitively by simple acid washing with an insignificant decrease in the active surface for consecutive adsorptions. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 43002.  相似文献   
3.
An experimental study was carried out to investigate the effects of a titanate coupling agent on the mechanical properties, moisture absorption, and thermal conductivity of talc‐filled high‐density polyethylene (HDPE). Talc (0–35 wt %) was used as reinforcement particulate filler in an HDPE matrix and samples were prepared in a micro‐compounder and an injection molding machine. Isopropyl tri(dioctyl)phosphate titanate (0.5 wt %) was used as coupling agent. Composites with and without coupling agent were evaluated for changes in mechanical and thermo‐physical properties, morphology, and void content. Addition of the titanate coupling agent most often resulted in an increase in stiffness and tensile strength. Furthermore, both the void content and the elongation at break of composites were reduced. Results also showed that the coupling agent had no effects on the thermal conductivity, thermal diffusivity, and specific heat capacity of the composites. In addition, it was observed that the coupling agent was more effective at low concentrations of filler. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 40449.  相似文献   
4.
This paper reports on SiGe NPN HBTs with unity gain cutoff frequency (fT) of 207 GHz and an fMAX extrapolated from Mason's unilateral gain of 285 GHz. fMAX extrapolated from maximum available gain is 194 GHz. Transistors sized 0.12×2.5 μm2 have these characteristics at a linear current of 1.0 mA/μm (8.3 mA/μm2). Smaller transistors (0.12×0.5 μm2) have an fT of 180 GHz at 800 μA current. The devices have a pinched base sheet resistance of 2.5 kΩ/sq. and an open-base breakdown voltage BVCEO of 1.7 V. The improved performance is a result of a new self-aligned device structure that minimizes parasitic resistance and capacitance without affecting fT at small lateral dimensions  相似文献   
5.
Real time B-scan ultrasonography was utilised on 318 eyes of 298 patients for evaluation of 285 (90%) eyes with opaque media; three (1%) eyes, with clear media but suspected intraocular abnormalities and for proptosis in 30 (9%) cases. Two hundred and nine (66%) eyes had one or more detectable abnormalities. The most common abnormality was retinal detachment (39%) followed by vitreous opacities (31%), eye ball size abnormalities (12%), intraocular foreign bodies (4%), posterior staphyloma (3%) and retinal detachment with vitreous opacities (2%). Twenty eight out of thirty patients evaluated for proptosis had abnormal orbital tissue patterns. Solid and cystic tissue patterns each accounted for 32% of the abnormal orbital studies followed by thyroid orbitopathy (25%), non specific (7%), and infiltrative (4%) tissue patterns. Detailed findings of B-scan ultrasonographic study is given in this paper. The paper reports further experience with the procedure in a developing country. In areas where other imaging techniques are not available the procedure is a valuable method of evaluating the eye and orbit for any detectable abnormalities and for planning management.  相似文献   
6.
The objective of this study was to examine the ruminal biohydrogenation of linoleic (18:2n-6) and linolenic (18:3n-3) acid during in vitro incubations with rumen inoculum from dairy cattle adapted or not to marine algae and with or without additional in vitro docosahexaenoic acid (DHA, 22:6n-3) supplementation. Treatments were incubated in 100-mL flasks containing 400 mg of freeze-dried grass, 5 mL of strained ruminal fluid, and 20 mL of phosphate buffer. Ruminal fluid was collected just before the morning feeding from 3 cows receiving a control diet (49% ryegrass silage, 39% corn silage, 1% straw, and 11% concentrate, fresh-weight basis) supplemented with marine algae for 21 d (adapted rumen fluid, aRF) or from the same cows receiving the control diet only for 14 d after marine algae supplementation was stopped (unadapted rumen fluid, uRF). In half of the incubation flasks, pure DHA (5 mg) was added as an oil-ethanol solution (100 mL). Incubations were carried out during 0, 0.5, 1, 2, 4, 6, and 24 h. After 24 h, in vitro addition of DHA resulted in greater amounts (mg/incubation) of 18:3n-3 (0.23, 0.43, 0.26, and 0.34 for aRF, aRF+DHA, uRF, and uRF+DHA), 18:2n-6 (0.14, 0.22, 0.15, and 0.20 for aRF, aRF+DHA, uRF, and uRF+DHA) and trans-11, cis-15-18:2 (0.27, 2.40, 0.06, and 2.21 for aRF, aRF+DHA, uRF, and uRF+DHA), whereas no effect of inoculum source was observed. Trans-11-18:1 accumulated after 24 h when aRF was incubated irrespective of in vitro DHA supplementation, whereas in incubations with uRF, accumulation of trans-11-18:1 only occurred when DHA was added (6.40, 4.35, 1.06, and 3.91 for aRF, aRF+DHA, uRF, and uRF+DHA). The increased amounts of trans-11-18:1 were due to the strong inhibition of the reduction to 18:0 because no 18:0 was formed when trans-11-18:1 accumulated after 24 h. The results of the current experiment shows hydrogenation of trans-11, cis-15-18:2 occurred in the absence of in vitro DHA only, whereas substantial hydrogenation of trans-11-18:1 to 18:0 only took place in incubations without DHA and with unadapted rumen inoculum, confirming the higher sensitivity of the latter process to DHA.  相似文献   
7.
This article investigates the Hall and ion‐slip impacts on the mixed convection flow of a Maxwell nanofluid over an expanding surface in a permeable medium. The impacts of Brownian movement and thermophoresis parameters, Soret, Dufour, viscous dissipation, chemical reaction, and suction parameters, are, moreover, considered. Using the similitude changes, the partial differential equations with regard to the momentum, energy, and concentration equations are transformed to an arrangement of nonlinear ordinary differential equations, which are handled numerically utilizing a spectral relaxation method (SRM). The impacts of noteworthy physical parameters on the velocities, thermal, and concentration distributions are investigated graphically. Moreover, the numerical values of skin‐friction coefficients, local Nusselt number, and Sherwood number for different values of the mixed convection parameter ( γ ) , Deborah number ( λ ) , Hall parameter ( β H ) , ion‐slip parameter ( β i ) , Dufour number (Du), and Soret number ( Sr ) are computed and tabulated. It is discovered that ascent in Deborah number reduces both the stream and transverse velocity profiles, while the inverse pattern is seen with augmentation in the mixed convection parameter. In addition, inverse patterns of the stream and transverse velocity profiles are seen with expansion in magnetic, Hall, and ion‐slip parameters. Besides this, the temperature and concentration disseminations decline with augmentation in Dufour number and chemical reaction parameters, respectively. It is likewise seen that both the skin‐friction coefficients lessen with expansion in Deborah number, and they ascend with upgrade in blended convection and ion‐slip parameters, while the opposite condition is noticed with augmentation in Hall parameter. Furthermore, the reverse trends of local Nusselt and Sherwood numbers are discovered with expansion in the Dufour and Soret numbers.  相似文献   
8.
Wireless Personal Communications - Through the use of UAV, the functional lifetime of WSN can be elongated in exchange for higher data delivery latency as the UAV replaces the multi-hop...  相似文献   
9.
A community based bacteriological study of weaning foods was conducted from November 1994 to August 1995 in six peasant associations, Jimma Zone. The households in the study community were found to be in poor sanitary conditions with cattle and pets living in the same room with humans, and the community gets water from unprotected sources. The predominant weaning foods in the study community were cereals. These and other foods given to weaning age children were found to be grossly contaminated, aerobic mesophilic bacterial counts being 10(5) cfu/ml of sample. The most frequent bacterial isolates were Enterobacter sp, Gram positive cocci including Staphylococcus aureus, Klebsiella sp., Citrobacter sp., and Escherichia coli in that order. Various factors such as unsafe water, unhygienic handling of food, storage of food at ambient temperature for a long time, poor domestic and personal hygiene may have contributed for the gross contamination of weaning foods in the study community. This calls for educating the community on the relationship between contamination of weaning foods and diarrhoeal diseases, and promoting measures such as reheating of weaning foods which have been kept at ambient temperature for a long time before serving infants and children.  相似文献   
10.

Here, we present the performance of a thermoelectric (TE) module consisting of n-type (La0.12Sr0.88)0.95TiO3 and p-type Ca3Co4?xO9+δ materials. The main challenge in this investigation was operating the TE module in different atmospheric conditions, since n-type has optimum TE performance at reducing conditions, while p-type has optimum at oxidizing conditions. The TE module was exposed to two different atmospheres and demonstrated higher stability in N2 atmosphere than in air. The maximum electrical power output decreased after 40 h when the hot side was exposed to N2 at 600°C, while only 1 h at 400°C in ambient air was enough to oxidize (La0.12Sr0.88)0.95TiO3 followed by a reduced electrical power output. The module generated maximum electrical power of 0.9 mW (~?4.7 mW/cm2) at 600°C hot side and δT?~?570 K in N2, and 0.15 mW (~?0.8 mW/cm2) at 400°C hot side and δT?~?370 K in air. A stability limit of Ca3Co3.93O9+δ at ~?700°C in N2 was determined by in situ high-temperature x-ray diffraction.

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