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61.
Carbon markets are increasingly conscious of the social and environmental ‘quality’ of credits delivered by CDM projects. Consequently carbon credits are no longer viewed as a homogenous good and buyers now differentiate between credits supplied by different types of CDM project. The objective of this paper is to classify CER buyers according to their attitudes towards and preferences for CDM sustainability labels. K-means clustering was used to segment a sample of buyers into two clusters. The results indicate that two clear clusters exist with distinct profile patterns. Moreover, the results of discriminant analysis confirmed that the two-cluster solution was valid. Finally, the results of the chi-square analysis and a cross-tabulation showed that these two clusters were significantly different in: organization type; level of paid up capital; perception of sustainable development benefits; perception of return on investment; perception of image of the sustainability labeling; participation in the voluntary market; the project priority; knowledge in the sustainability label; attitude towards the host country's duty; and their willingness to pay. 相似文献
62.
Jing Gao Jiang You Zhihong Huang Sandy Cochran George Corner 《International Journal of Thermophysics》2012,33(3):495-504
Tissue-mimicking phantoms, including bovine serum albumin phantoms and egg white phantoms, have been developed for, and in
laboratory use for, real-time visualization of high intensity focused ultrasound-induced thermal coagulative necrosis since
2001. However, until now, very few data are available concerning their thermophysical properties. In this article, a step-wise
transient plane source method has been used to determine the values of thermal conductivity, thermal diffusivity, and specific
heat capacity of egg white phantoms with elevated egg white concentrations (0 v/v% to 40 v/v%, by 10 v/v% interval) at room
temperature (~20 °C). The measured thermophysical properties were close to previously reported values; the thermal conductivity
and thermal diffusivity were linearly proportional to the egg white concentration within the investigation range, while the
specific heat capacity decreased as the egg white concentration increased. Taking account of large differences between real
experiment and ideal model, data variations within 20 % were accepted. 相似文献
63.
韩冰 《建设科技(建设部)》2021,(20):17-21
木材行业是中国重要的基础产业,随着国民经济和人民水平生活水平的不断提高,对木材需求量快速上升,然而中国对天然林资源的使用,实行的是禁伐和限伐,因此国内木材供应量远远满足不了国内需求.作为目前世界上最主要的木业加工、生产及出口国,中国是全球最大的木材进口国之一.笔者通过详解近几年中国木材进口数据,原木及锯材的进口情况,从进口的树种,来源国,价格等全方面剖析,并阐述数据背后的原因,细致描述了中国木材进口的趋势及变化. 相似文献
64.
Mohammed Hefni Christopher McEntyre Michael Lever Sandy Slow 《Food Analytical Methods》2016,9(2):292-299
The importance of dietary betaine is increasingly recognized. The aim of this study was to develop a simple high-performance liquid chromatography with standard ultraviolet spectrometric detection (HPLC-UV) method for betaine (N,N,N-trimethylglycine) determination in foods after derivatization. Two methods were used for betaine derivatization. Thereafter, derivatized betaine was quantified using HPLC-UV, and the results were compared with liquid chromatography mass spectrometry (LC-MS). The established derivatizing agent 2′-naphthacyl triflate and a novel derivatizing agent 2-bromo-2′-acetonaphthone produced the same cationic derivative when they react with betaine. The calibration curves were linear up to 1000 μmol/L (R 2?=?0.9974 for 2′-naphthacyl triflate and 0.9995 for 2-bromo-2′-acetonaphthone). The limit of detection was 1 μmol/L for both methods (2′-naphthacyl triflate and 2-bromo-2′-acetonaphthone), confirming sufficient sensitivity for betaine quantification in foods. The average recovery from different food matrices (wheat flour and spinach) (n?=?12) was 99?±?9 %, 95?±?10 %, and 101?±?8 % for LC-MS, 2′-naphthacyl triflate, and 2-bromo-2′-acetonaphthone, respectively. Inter- and intra-assay coefficients of variation (CVs) in the control samples (whole wheat flour) were below 10 %. Quantitative results for foods analyzed using 2′-naphthacyl triflate and 2-bromo-2′-acetonaphthone were comparable to LC-MS (R 2?=?0.992 and 0.990), respectively. The highest betaine content (~160 mg/100 g) was found in spinach followed by faba bean, wheat flour, and beetroot. These methods can be widely used for betaine quantification because of the simplicity of the derivatization procedures, and the commercial availability of the derivatizing reagent (2-bromo-2′-acetonaphthone) or through the relatively easy synthesis of 2-naphthacyl triflate. 相似文献
65.
Burns IG Zhang K Turner MK Lynn J McClement S Hand P Pink D 《Journal of the science of food and agriculture》2011,91(12):2217-2233
BACKGROUND: The causes of the natural variation in nitrate accumulation and associated traits are studied using a diverse population of 48 mature lettuce accessions grown hydroponically in winter and summer seasons. Information on the effects of genotype, environment and their interactions will inform future selection strategies for the production of low‐nitrate varieties more suited to meeting EU requirements for harvested produce. RESULTS: The effects of genotype (G), environment (E) and G × E interactions were all significant, with nitrate concentrations lower but covering a wider range in summer. Concentrations of nitrate‐N were positively correlated with those of water and total‐N and negatively with assimilated‐C in the shoot in both seasons, with all relationships partitioned according to morphotype and/or seasonal type. Corresponding relationships between nitrate‐N and assimilated‐N or with shoot fresh or dry weight were generally weak or inconsistent. Nitrate concentrations at an early growth stage were strongly related to those at maturity in winter, but not in summer when light levels were less variable. CONCLUSION: The effects of genotype and environment on nitrate accumulation in lettuce are strongly influenced by morphotype, with most G × E interactions between accessions within the same morphotype predominantly of the non‐crossover type. All low‐nitrate‐accumulating genotypes have increased concentrations of organic solutes (concentration regulation) and reduced water (volume regulation) to help stabilise osmotic potential within the shoots. Variability in nitrate accumulation arises more from differences in uptake than in efficiency of its chemical reduction. Genotypic differences in nitrate accumulation can be masked by changes in head morphology during maturation, provided that they are not confounded by substantial changes in intercepted light. Recent selection strategies do not appear to have produced lower‐nitrate‐accumulating cultivars. Copyright © 2011 Society of Chemical Industry 相似文献
66.
Ken Houben Stefanie Christiaens Doungla E. Ngouémazong Sandy Van Buggenhout Ann M. Van Loey Marc E. Hendrickx 《Food and Bioprocess Technology》2014,7(9):2570-2580
Tomato and carrot were subjected to a split-stream process designed to produce a tomato–carrot suspension with reduced consistency. Raw tomatoes, containing pectinmethylesterase and endo-polygalacturonase, were mixed with thermally pretreated (blanched versus cooked) carrots containing different levels of solubilized pectin. After mixing the vegetables, tomato pectinases were shown to act on both tomato and carrot pectin in case an incubation step at medium temperature level (30 min, 40 °C), to allow enzyme action, was performed. Carrot pectin, when present in a mix of tomato and blanched (5 min, 95 °C) carrot, was solubilized as well as depolymerized, whereas depolymerization of the thermo-solubilized carrot pectin by the tomato pectinases was observed in the tomato–carrot purée containing cooked (30 min, 95 °C) carrots. The final serum pectin properties were however similar for both purée types. Carrot contributed more to the consistency of the purée mix compared with tomato but by stimulating the action of the tomato pectinases at mild temperature (30 min, 40 °C), this contribution was lost which resulted in a consistency reduction of the purée mix. This purée liquefaction was larger for the tomato–carrot purée containing blanched instead of cooked carrots. Based on the results, it is suggested that the liquefying effect is related to solubilization and degradation of pectin that is counteracted by a reduction in particle size. The purée mix containing cooked carrot showed in this respect smaller particle sizes than the mix containing blanched carrot. 相似文献
67.
Michael Reinwald Ben Moseley Alexandre Szenicer Tarje Nissen-Meyer Sandy Oduor Fritz Vollrath Andrew Markham Beth Mortimer 《Journal of the Royal Society Interface》2021,18(180)
African elephants (Loxodonta africana) are sentient and intelligent animals that use a variety of vocalizations to greet, warn or communicate with each other. Their low-frequency rumbles propagate through the air as well as through the ground and the physical properties of both media cause differences in frequency filtering and propagation distances of the respective wave. However, it is not well understood how each mode contributes to the animals’ abilities to detect these rumbles and extract behavioural or spatial information. In this study, we recorded seismic and co-generated acoustic rumbles in Kenya and compared their potential use to localize the vocalizing animal using the same multi-lateration algorithms. For our experimental set-up, seismic localization has higher accuracy than acoustic, and bimodal localization does not improve results. We conclude that seismic rumbles can be used to remotely monitor and even decipher elephant social interactions, presenting us with a tool for far-reaching, non-intrusive and surprisingly informative wildlife monitoring. 相似文献
68.
Kraimer Maria L.; Seibert Scott E.; Wayne Sandy J.; Liden Robert C.; Bravo Jesus 《Canadian Metallurgical Quarterly》2011,96(3):485
This study examines antecedents and behavioral outcomes of employees' perceptions of organizational support for development. We first propose that employees' past participation in formal developmental activities and experience with developmental relationships positively relate to their perceptions of organizational support for development. We then propose that perceived career opportunity within the organization moderates the relationship between organizational support for development and employee performance and turnover. Using a sample of 264 exempt-level employees and their supervisors, we found that participation in training classes, leader–member exchange, and career mentoring were each positively related to employees' perceptions of organizational support for development. We also found support for the moderator hypotheses. Specifically, development support positively related to job performance, but only when perceived career opportunity within the organization was high. Further, development support was associated with reduced voluntary turnover when perceived career opportunity was high, but it was associated with increased turnover when perceived career opportunity was low. Our study demonstrates that social exchange and career motivation theory work together to explain when and how employees' perceptions of organizational support for development relate to turnover and job performance. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
69.
Qiu Z Sadiq MR Démoré C Parker MF Marin P Mayne K Cochran S 《IEEE transactions on ultrasonics, ferroelectrics, and frequency control》2011,58(9):1793-1803
Piezoelectric single crystal materials such as (x)Pb(Mg(1/3)Nb(2/3))O(3-)(1-x)PbTiO(3) (PMN-PT) have, by some measures, significantly better performance than established piezoelectric ceramics for ultrasound applications. However, they are also subject to phase transitions affecting their behavior at temperatures and pressures encountered in underwater sonar and actuator applications and in non-destructive testing at elevated temperatures. Materials with modified compositions to reduce these problems are now under development, but application-oriented characterization techniques need further attention. Characterization with temperature variation has been reported extensively, but the range of parameters measured is often limited and the effects of pressure variation have received almost no attention. Furthermore, variation in properties between samples is now rarely reported. The focus of this paper is an experimental system set up with commercially available equipment and software to carry out characterization of piezoelectric single crystals with variation in temperature, pressure, and electrical bias fields found in typical practical use. We illustrate its use with data from bulk thickness-mode PMN-29%PT samples, demonstrating variation among nominally identical samples and showing not only the commonly reported changes in permittivity with temperature for bulk material but also significant and complicated changes with pressure and bias field and additional ultrasonic modes which are attributed to material phase changes. The insight this provides may allow the transducer engineer to accelerate new material adoption in devices. 相似文献
70.
Lin CY Wen LL Lin LY Wen TW Lien GW Chen CY Hsu SH Chien KL Sung FC Chen PC Su TC 《Environmental science & technology》2011,45(24):10691-10698
In animals, perfluorinated chemicals (PFCs), specifically perfluorooctanoic acid (PFOA) and perfluorooctane sulfate (PFOS), function as peroxisome proliferator-activated receptor (PPAR) alpha agonists. However, the relevance of animal (primarily rodent) data to humans is unresolved. While plasma adiponectin level is very responsive to PPAR gamma agonist drugs, it has not been determined whether adiponectin level is related to serum PFCs concentrations. In the present study, 287 subjects (12-30 years of age) were recruited to determine the relationship between serum level of PFCs and serum level of adiponectin. The results showed males had higher serum PFOS concentrations than females and that those with metabolic syndrome had lower serum PFOA than controls. Besides, it showed regional elevations of the perfluoroundecanoic acid (PFUA) (median concentration: 7.11 ng/mL) in the study subjects. No relationship of PFOA, PFOS, PFUA, and the sum of all four PFCs was found to glucose homeostasis, adiponectin level, lipid profile, and inflammatory markers. The median and the range of perfluorononanoic acid (PFNA) concentration (in ng/mL; for four categories corresponding to the <50, 50-74, 75-89, and ≥90th percentiles) were 0.38 (0.38-1.68), 3.22 (1.73-4.65), 5.85 (4.75-8.29), 10.56 (8.40-25.40), respectively. After controlling for confounding factors, multiple linear regression analysis revealed that the mean natural log-transformed level of adiponectin increased significantly across categories of PFNA (in ng/mL; 8.78, 8.73, 9.06, 9.36; P for trend = 0.010 in the full model). In conclusion, higher serum PFNA concentration is associated with elevated serum adiponectin concentration. 相似文献