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141.
中国造纸工业2007年度报告 总被引:13,自引:9,他引:4
发布了2007年度中国造纸工业的各项数据,对行业的经济运行情况进行了分析。 相似文献
142.
湖南省造纸原料资源十分丰富,近20多年来湖南造纸工业发展迅速。2006年,全省共有造纸企业743家,纸及纸板产量240万吨,占全国总产量的3.69%,居全国第8位。2007年,全省纸及纸板产量249.3万吨。造纸工业已被确定为湖南的优势传统产业。 相似文献
143.
This study compared locomotion, hoof health, and lameness of dairy cows confined in either indoor free stalls (FS) or 1 of 3 out-wintering pad (OWP) designs. Out-wintering pad treatments were 1) uncovered OWP with a concrete feed apron (UP); 2) covered OWP with a concrete feed apron (CO); and 3) uncovered OWP on top of which grass was ensiled so that the cows could self-feed (SP). Cows were assigned to treatment at drying off using a randomized complete block design. They remained on treatment until calving, when they were turned out to pasture. Sole lesions, heel erosion, dermatitis, and claw hardness on both hind feet were scored according to severity at assignment to treatment, at calving, and 9 and 14 wk postpartum. Locomotion score was recorded weekly after calving for 14 wk. Incidence of clinical lameness was recorded during the treatment period and in the subsequent lactation. Treatment had no effect on sole lesion score, but scores increased over time (calving = 5.5 ± 1.3, wk 9 = 10.8 ± 1.3, wk 14 = 14.2 ± 1.3, mean ± SE). Self-fed cows had higher heel erosion scores (6.4 ± 0.4) than FS and CO cows (4.7 ± 0.4 and 4.7 ± 0.4, respectively) at calving. Cows on SP had the highest dermatitis scores [1.14 (0-2) mean (interquartile range)] and FS cows the lowest [0.51 (0-0)]. Hooves were hardest at assignment to treatment (43.9 ± 0.6) with a significant reduction in hardness at calving (40.0 ± 0.6). The hooves of CO cows were harder than those of SP and UP cows (CO = 43.3 ± 0.7, SP = 41.7 ± 0.7, UP = 41.7 ± 0.7, Shore D scale). There was no treatment effect on locomotion scores or lameness incidence. Higher dermatitis scores and heel erosion in SP may be due to exposure to excreta and moisture, because the SP treatment had no manure removal system at the feed face. In FS, the alleys and the feed face were cleaned regularly by automatic scraper, explaining the lower dermatitis scores recorded indoors. Providing shelter for OWP likely reduced exposure to environmental moisture. This ensured that the hooves of CO cows remained as hard as those of FS cows. Low correlations between hardness and pathologies indicate that other factors are involved in the development of hoof pathologies. Confining dry dairy cows on OWP does not increase locomotion scores or lameness incidence. 相似文献
144.
Jonathan D. French † Helen M. Chan Martin P. Harmer Gary A. Miller 《Journal of the American Ceramic Society》1996,79(1):58-64
The temperature dependence of the fracture toughness of ceramics exhibiting duplex microstructures was studied relative to their single-phase constituents using two test methods: bend testing of chevron-notched beams, and the indentation-crack-length technique. The two materials systems studied were Al2 O3 : c -ZrO2 (Y) and A12 O3 :Y3 A1S O12 (YAG), and the testing temperature ranged from room temperature to 1200°C. The study showed that in both systems the duplex materials showed higher toughness values than their single-phase constituents above 800°C. This result was attributed to the contribution of low-energy interphase boundaries to the overall composite toughness. Indentation crack length measurements gave toughness values and trends comparable to those determined by the chevronnotched beam method. By comparing the results of the two test methods it was possible to demonstrate that the indentation calibration constant (ξ) shows no significant temperature or material dependence. For the zirconia-containing materials, however, indentation at elevated temperatures is accompanied by significant localized plasticity, which suppressed the radial cracking. Under such conditions, some caution is warranted, since localized plasticity can lead to an overestimation of the fracture toughness. 相似文献
145.
Finnish Tunnelling Association 《Tunnelling and Underground Space Technology incorporating Trenchless Technology Research》1992,7(4):399-405
During October-November 1991, the Finnish Tunnelling Association conducted a joint survey with the Rock Engineering Laboratory of the Helsinki University of Technology. The intent of the survey was to investigate the notions of rock construction and rock spaces held by city planners of new construction areas. The questionnaire was sent to 37 architects working in city planning, 33 of whom (about 90%) were interviewed. The survey found a relationship between incomplete knowledge, or obsolete knowledge, and negative attitudes toward rock construction. Those with rock construction experience believed more strongly than other that rock spaces are more easily fitted into planned areas and the urban structure, than their effect on the city panorama is better, and that their construction is more economical than construction oboveground. 相似文献
146.
本期杂志记载了香港近10年的建筑历史,不只因为这是一个对建筑批判性的评估(很少在香港本地媒体批判性地讨论建筑),及1997年回归后10年来的都市发展,亦预示着在这个年代中香港正发展着一种大趋势,让大众去表达对发展,可持续发展、设计质量、竞赛、与内地融合及本土文物建筑保护的态度及意见。我们的城市正处在危机或再生的边缘,能否通过建筑师的努力以香港著名的拼搏精神推动我们的建设?本期分4个部分:回顾近10年来的重大工程,建筑师学会大奖及对未来建筑的展望。回顾和展望这两个部分主要以回顾及前瞻方式指出香港建筑的急切都市问题。我们的主题“好、差、丑” 相似文献
147.
French Doran C.; Eisenberg Nancy; Vaughan Julie; Purwono Urip; Suryanti Telie A. 《Canadian Metallurgical Quarterly》2008,44(2):597
This study assessed the relation between religious involvement and multiple indices of competence in 183 eighth- and ninth-grade Indonesian Muslim adolescents (M = 13.3 years). The authors assessed spirituality and religiosity using both parent and adolescent reports, and social competence and adjustment using multiple measures and data sources. Structural equation modeling analyses revealed that parent and adolescent reports of religiosity and spirituality yielded a single religious involvement latent variable that was related to peer group status, academic achievement, emotional regulation, prosocial behavior, antisocial/problem behavior, internalizing behavior, and self-esteem. The consistency of relations between religious involvement and competence may be in part attributable to the collectivist context of religion in West Java, Indonesia, within which people exhibit strong beliefs in Islam and religion permeates daily life. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
148.
149.
ZHANG Jinghui LI Dajun ZHAO Jiuzhou JIA Jun Harbin Institute of Technology Harbin ChinaLI Jianhui Heilongjiang Association for Science Technology Harbin China 《金属学报(英文版)》1991,4(9):179-183
The microstructure and martensite substructure of as-cast martensitic high-Cr cast iron byinjection microalloying have been studied by usig SEM and TEM.The relationship betweendistribution of alloying elements and phase formation of carbide,as well as various branchingand distortion of carbide,have been analysed by X-ray diffractometer and EPMA. 相似文献
150.