首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   16篇
  免费   4篇
电工技术   4篇
化学工业   2篇
建筑科学   1篇
轻工业   4篇
一般工业技术   3篇
冶金工业   5篇
自动化技术   1篇
  2022年   1篇
  2018年   1篇
  2017年   1篇
  2015年   4篇
  2014年   2篇
  2013年   2篇
  2008年   1篇
  2002年   1篇
  1999年   1篇
  1998年   1篇
  1994年   1篇
  1974年   1篇
  1970年   1篇
  1969年   1篇
  1967年   1篇
排序方式: 共有20条查询结果,搜索用时 15 毫秒
1.
2.
3.
Dackere is a granulated food made from tubers or cereals flours by women in rural areas of Northern Cameroon. The processing of the semolina faces some constraints that affect the quality and hence the potential to improve the incomes of producers. The objectives of this work were to identify and characterize the processing steps involved in the production of dackere and evaluate the physicochemical and hedonic characteristics of this food. Four groups of farmers consisting of organized and specialized women in dackere processing were used for this purpose and then followed up in their production site. The results obtained revealed that dackere was manufactured from either tubers or cereals based on the available food materials: sweet potato, cassava, corn, millet, fonio, and mixture of sweet potato/corn. Generally, the processes involved included hydrating the flour with water, granulating manually, steam cooking, and eventually drying. All these processes were done in a non-replicable manner using traditional equipment. The physicochemical characterization revealed that dackeres were in general rich in starch (60.63 to 94.99 g/100 g) and poor in proteins (0.77 to 4.42 g/100 g). Digestible starch varied from 34.9 g/100 g for corn dackere to 66.6 g/100 g for cassava and sweet potatoes dackeres, and the index of whiteness varied from 58.8 for sweet potatoes dackere to 75.8 for cassava and corn dackeres. Significant variations were observed among producers. Consumers more appreciated the sweet potato/corn dackere mixture which was associated by principal component analysis to high swallowing ability, taste, and adherence in mouth. However, they were irregular in size and brown in color, characteristics negatively correlated to acceptability.  相似文献   
4.
Weight gain is a hallmark of decreased estradiol (E2) levels because of menopause or following surgical ovariectomy (OVX) at younger ages. Of note, this weight gain tends to be around the abdomen, which is frequently associated with impaired metabolic homeostasis and greater cardiovascular risk in both rodents and humans. However, the molecular underpinnings and the neuronal basis for these effects remain to be elucidated. The aim of this study is to elucidate whether the kappa-opioid receptor (k-OR) system is involved in mediating body weight changes associated with E2 withdrawal. Here, we document that body weight gain induced by OVX occurs, at least partially, in a k-OR dependent manner, by modulation of energy expenditure independently of food intake as assessed in Oprk1−/−global KO mice. These effects were also observed following central pharmacological blockade of the k-OR system using the k-OR-selective antagonist PF-04455242 in wild type mice, in which we also observed a decrease in OVX-induced weight gain associated with increased UCP1 positive immunostaining in brown adipose tissue (BAT) and browning of white adipose tissue (WAT). Remarkably, the hypothalamic mTOR pathway plays an important role in regulating weight gain and adiposity in OVX mice. These findings will help to define new therapies to manage metabolic disorders associated with low/null E2 levels based on the modulation of central k-OR signaling.  相似文献   
5.
In this paper, we investigate the effect of partial discharges (PDs) on the thermal breakdown voltage of oil‐impregnated paper (OIP). A disk‐shaped cavity in a stack of paper sheets formed the PD source. The paper sample was exposed to PDs for 18 h. Dielectric spectroscopy measurements were performed on the samples before and after exposure to PD activity. The dielectric spectroscopy results showed a big change in the real and imaginary part of the permittivity. These results were used to calculate the activation energy and heat losses inside the insulation. In order to investigate the possibility of thermal breakdown in the system, the OIP system was simulated by using the FEM software COMSOL Multiphysics. The heat produced by PD pulses and dielectric losses was considered in the simulation. The results show that for the OIP insulation, PD activity can reduce the thermal breakdown voltage by a factor up to 4 times. © 2015 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc.  相似文献   
6.
Poly(acrylic acid) (PAA) is an important polymer frequently used as a superabsorbent in health and hygiene products. As a polyelectrolyte that swells with absorption of water it has potential application in other fields including drug delivery, tissue scaffolds, actuators, and desiccation and humidity control. To be useful in such applications the membrane's mechanical integrity must be maintained while optimizing its moisture absorption properties. In this work PAA membranes are electrospun with lysine as cross‐linking agent. The effects of varying the concentration of the lysine on the cross‐link density and consequently on the thermo‐ and hygro‐mechanical properties of the membranes are studied through electron microscopy, FTIR spectroscopy, and dynamic mechanical thermal analysis (DMTA). Isothermal glass transitions are shown to occur with varying moisture content. The moisture content (or relative humidity) at which the transition occurs is reduced by increasing temperature and can be controlled by varying the cross‐link density. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41252.  相似文献   
7.
We compared 2 methods for identifying lame cows and estimating the prevalence of lameness in tiestalls. Cows (n = 320) in 9 tiestall herds were scored as lame both by the presence of limping while walking and by stall lameness scores (SLS). The SLS was based on the number of the following behaviors that the cow showed while standing in the tiestall: weight shifting, standing on the edge of the stall, uneven weight bearing while standing, and uneven weight bearing while moving from side to side. Two observers watched video-recordings of the cows. Intraobserver agreements for the 4 SLS behaviors ranged from 92 to 100%, and interobserver agreement ranged from 81 to 100%. The overall prevalence of lameness based on an SLS of ≥2 was similar to that of limping (39 vs. 40%). The sensitivity of the classification based on the SLS was 0.63 and the specificity was 0.77 in identifying cows with a limp; accuracy varied across farms from 62.2 to 80.4%, with a mean of 71.7%. A cow with an SLS of ≥2 had 4.88 times the odds of limping than a cow with an SLS of <2. The prevalence of lameness on farms based on SLS was highly correlated with the prevalence of limping (Pearson correlation = 0.88; n = 9), and prevalence estimates from the 2 methods diverged most when the mean herd prevalence was lower. The SLS method provides an estimate of the prevalence of lameness in tiestall herds comparable with traditional gait scoring, but does not require that the cows be untied. The SLS method could be used to improve lameness detection on tiestall farms and obtain estimates of lameness prevalence without the need to walk the cows.  相似文献   
8.
Method This paper presents methods of measuring the longitudinal relaxation time using inversion recovery turbo spin echo (IR-TSE) and magnetization-prepared rapid gradient echo (MPRAGE) sequences, comparing and optimizing these sequences, reporting T 1 values for water protons measured from brain tissue at 1.5, 3, and 7T. T 1 was measured in cortical grey matter and white matter using the IR-TSE, MPRAGE, and inversion recovery echo planar imaging (IR-EPI) pulse sequences. Results In four subjects the T 1 of white and grey matter were found to be 646±32 and 1,197±134ms at 1.5T, 838±50 and 1,607±112ms at 3T, and 1,126±97, and 1,939±149ms at 7T with the MPRAGE sequence. The T 1 of the putamen was found to be 1,084±63ms at 1.5T, 1,332±68ms at 3T, and 1,644±167ms at 7T. The T 1 of the caudate head was found to be 1,109± 66ms at 1.5T, 1,395±49ms at 3T, and 1,684±76ms at 7T. Discussion There was a trend for the IR-TSE sequence to underestimate T 1 in vivo. The sequence parameters for the IR-TSE and MPRAGE sequences were also optimized in terms of the signal-to-noise ratio (SNR) in the fitted T 1. The optimal sequence for IR-TSE in terms of SNR in the fitted T 1 was found to have five readouts at TIs of 120, 260, 563, 1,221, 2,647, 5,736ms and TR of 7 s. The optimal pulse sequence for MPRAGE with readout flip angle = 8° was found to have five readouts at TIs of 160, 398, 988, 2,455, and 6,102ms and a TR of 9 s. Further optimization including the readout flip angle suggests that the flip angle should be increased, beyond levels that are acceptable in terms of power deposition and point-spread function.  相似文献   
9.
Monitored eye movements in each of 3 studies with 20, 19, and 18 undergraduates, respectively, while Ss were given 8 study trials on a 7-item paired-associate list. Ss were then subjected to a single test trial of associative matching (Exp. I), response production (Exp. III) or stimulus and response production (Exp. IV). A 4th study with 42 Ss, (Exp. II), without eye movement monitoring, involved 3 groups of Ss given either 2, 4, or 6 study trials followed by a single test trial of associative matching. Results, with the exception of Exp. I, were generally consistent with a 2-stage notion of verbal paired-associate learning. (French summary) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
10.
Monitored eye movements during the learning and relearning of a 7-pair A-B list for 64 undergraduates in 4 groups, 2 of these being required to learn an AC list in the interim and 2 being given interpolated activity designed to produce minimal interference with the relearning of A-B. Retroactive inhibition was demonstrated and the fixation and eye-movement data for original learning were consistent with earlier studies and with a 2-stage interpretation of paired-associate learning. The visual monitoring data for relearning were more compatible with a selector mechanism account of retroactive inhibition than with one of competition, unlearning, or trace decay. (French summary) (24 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号