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1.
 It is proved that the system of word equations x i 1=y i 1 y i 2y i n , i=1, 2,…, ⌈n/2⌉ +1, has only cyclic solutions. Some sharpenings concerning the cases n=5, 7 and n≥9 are derived as well as results concerning the general system of equations x i 1 x i 2x i m =y i 1 y i 2y i n , i=1, 2,… . Applications to test sets of certain bounded languages are considered. Received: 18 May 1995/2 January 1996  相似文献   
2.
Nitrite intake from the consumption of cured meat and tap water was estimated for Finnish children of 1, 3 and 6 years as well as Finnish adults of 25–74 years. Nitrite content in the foods was measured by capillary electrophoresis, and was then used together with individual food consumption data from the FINDIET 2007 and DIPP studies in a stochastic exposure assessment by a Monte Carlo Risk Assessment (MCRA) program. Nitrite intake from additive sources and tap water was assessed, and more than every 10th child between the ages 3 and 6 years was estimated to have a nitrite intake exceeding the acceptable daily intake (ADI) of nitrite. The high exposure levels were caused by frequent consumption of large portions of sausages, up to 350 g day–1 or 750 g in 3 days, among the children. Median nitrite intake from cured meat was 0.016, 0.040, 0.033 and 0.005 mg kg–1 body weight day–1 for children of 1, 3 and 6 years and adults, respectively. Bayesian estimation was employed to determine safe consumption levels of sausages and cold cuts for children, and these results gave rise to new national food consumption advice.  相似文献   
3.
Plant lignans are converted to mammalian forms, enterodiol and enterolactone, in the colon. Enhanced plasma or urinary enterolactone levels have been associated with lowered risk of cardiovascular diseases and breast cancer. Processed rye bran and its fractions were compared to ascertain the fermentation rates of fermentable carbohydrates and the bioconversion of lignans. Rye bran was extruded and treated with a food‐grade xylanase. Part of the xylanase‐treated rye bran was separated into a soluble rye bran extract and an insoluble residue, and a part of the xylanase‐treated rye bran was freeze‐dried without separation. All the samples were digested by pepsin and pancreatin and subsequently fermented with a human faecal inoculum in vitro. The consumption of carbohydrates, the productions of short‐chain fatty acids (SCFA), enterodiol and enterolactone were followed as a function of time. The soluble rye bran extract showed the fastest fermentation rate and the highest extent of fermentation determined as the consumption of neutral sugar residues (arabinose, xylose and glucose), the production of SCFA and the formation of enterodiol and enterolactone. Xylanase treatment enhanced the fermentation rate of extruded rye bran. An even a higher fermentation rate was observed for rye bran extract containing soluble carbohydrates. The amount of enterolactone precursors in rye seemed to be too low for enterolactone formation using an amount of substrate suitable for carbohydrate fermentation. However, xylanase treatment enhanced the availability of plant lignans from rye bran, as enterodiol formation was increased by the use of xylanase. Copyright © 2005 Society of Chemical Industry  相似文献   
4.
机械制造商未来服务理念的一个策略性选择   总被引:1,自引:0,他引:1  
一、简介 当制造企业以其核心业务为重点时,业务外包和外委服务的方式成为资产管理的一个选择。新的生产模式是建立在协作网络的基础上的,其中如维修、设计和物流由服务者提供,并与企业的工作紧密协作。未来价值网络可能取代价值链,在价值网络中,对于产品和提供的服务,公司提供补充功能和所有资本都是必要的。  相似文献   
5.
Nitrogen export from diffuse and point sources and its retention in the major river basins of Finland is quantified and discussed. The estimated total export from river-basins in Finland was 119,000 tonnes N a(-1) for the period 1993 to 1998 based on N export from different land use types defined in a GIS-based assessment model, incorporated with estimates of N inputs from atmospheric deposition and point sources. Agriculture contributes 38% of the total export, varying in the range 35-85% in the south-western basins and 0-25% in the northern basins. This estimate of N export from agriculture was based on regional N balances together with data from small agricultural research catchments. Forestry contributes on average 9%, with increasing dominance towards eastern and northern parts of the country: from 2% to 15% in the southern-mid-western Finland basins to 10-30% in the large northern basins. 'Background' N export from forests on both mineral and organic soils contributes 27% on average; in the northern basins it may contribute from 40% up to 90% of the total load. The estimate was calculated based on practically all data available from 42 small, experimental catchments in Finland. Of the total N input to Finnish river-systems, 0% to 68% was retained in surface waters and/or peatlands, with a mean retention of 22%. The highest retention of N (36-61%) was observed in the basins with the highest lake percentages. The lowest retention (0-10%) of N was in the coastal basins with practically no lakes. In the national N mass balance, 38,000 tonnes N a(-1) (32%) was estimated as lake retention and 4,000 tonnes N a(-1) (3%) as retention in peatlands. On the basis of mass balances and sensitivity analysis, retention was in most cases estimated to be in the range of 7.5-12.5 kg ha(-1)a(-1) in lakes and 0-1.5 kg ha(-1)a(-1) in peatlands. The model results were tested using the split-sample technique and uncertainty estimates for different data sources are provided and discussed.  相似文献   
6.
Cellular polystyrene (EPS) is the most commonly used cellular thermoplast whose main applications are insulation and packages. One of its new applications is core material in building elements, and this poses higher requirements for strength. This is particularly evident in self-supporting roof elements. This study presents a method for determining the fusion strength between beads in cellular polystyrene and the dependence of this strength on processing. This method has also enabled us to determine the adhesion of cellular polystyrene beads to other materials, such as glass fibre, and it allows measurement of the fusion strength between EPS beads without the influence of porosity. Fusion strength was found to have a characteristic behaviour. It has an absolute upper limit, and fusion forces approximate this limit asymptotically as heating time is prolonged (this increase is dependent on the energy content of the steam).  相似文献   
7.
8.
The relationship of the extent and composition of coronary lesions and the degree of cardiac hypertrophy to anthropometric indicators of abdominal fatness and the amount of intra-abdominal fat was investigated in a group of 32 forensic autopsy cases that consisted of sudden deaths from violent causes of previously healthy men under 40 years of age. Body height and weight, waist and hip circumferences, and the thickness of the subscapular and abdominal subcutaneous fat were measured; the body mass index (BMI) and waist-to-hip ratio (WHR) were calculated; and omental, mesenteric, and perirenal fat deposits and the heart were weighed. The degree of coronary narrowing was determined visually, and the extent of coronary lesions was measured by planimetry. The thickness of the intima and intima-media was measured by computerized image analysis. Intimal macrophage foam cells and smooth muscle cells were detected by immunohistochemistry. Significant positive correlations were found between WHR and the overall degree of coronary narrowing and the intima-media thicknesses of the left anterior descending artery and right coronary artery when adjusted for age. Intima-media thickness was also related to tertiles of WHR. Heart weight indexed to height showed a significant positive correlation with BMI, waist circumference, WHR, and the size of intra-abdominal fat deposits, of which WHR was the best predictor of mild cardiac hypertrophy. The results indicate that the severity of clinically silent lesions in the atherosclerosis-prone regions of the coronary arteries is associated with WHR in young male individuals who also have mild myocardial hypertrophy associated with abdominal fatness and an accumulation of intra-abdominal fat. These associations between fat distribution and early cardiovascular changes point to a powerful need for preventive action with respect to weight gain in young men to alleviate progression of the lesions.  相似文献   
9.
ABSTRACT: The effect of relative humidity (RH) (20 °C: RH 11%, 54%) on oxidative stability microencapsulated sea buckthorn seed oil was studied using bulk oil as a reference. Microcapsules were prepared by spray-drying using maltodextrin-gum arabic (MD/GA) and corn starch sodium octenyl succinate derivate (HiCap) as the wall materials. The influence of the physical state of the wall material was also evaluated. Under dry conditions, the microencapsulated oils were most stable, but the oxidation of the bulk oil was accelerated. At 20 °C and at RH 11%, the peroxide value of the bulk oil exceeded 20 meq/kg within 1 wk. Microencapsulation prolonged the shelf-life of the oil from 1 wk to 2 mo at 20 °C, when the encapsulating matrix was in glassy state. In conditions in which the HiCap matrix was in a rubbery state (RH 54%, 20 °C), the oxidation proceeded very quickly, reaching a peroxide value of 20 meq/kg just after 1 wk. Caking and collapse of the microcapsule powder were observed in the rubbery state. At accelerated conditions (50 °C: RH 11%, 30%, 45%), the oxidation was noticeably fast, not only in the bulk oil but also in the MD/GA matrix, even in the glassy state. The behavior in the HiCap matrix was more complex as the amount of peroxides started to decrease in time. This was assigned to the structural collapse in HiCap microcapsules. The behavior of the microencapsulated oils under accelerated conditions did not correlate with their behavior at 20 °C.  相似文献   
10.
The purpose of this paper is to apply concepts of the diffusion of innovations research in thestudy of the international diffusion of a formerly national scientific journal, Annales ZoologiciFennici. The study was conducted using bibliometric methodology. The diffusion of the journalwas described through citations of the journal and through the development of the nationaldistribution of its contributors. The compatibility of the journal as well as the decrease ofcomplexity were found to have an influence on diffusion. Bibliometric methods were able torepresent the international diffusion of a scientific journal.  相似文献   
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