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81.
82.
O.?TreuschEmail author A.?Hofenauer F.?Tr?ger J.?Fromm G.?Wegener 《Wood Science and Technology》2004,38(5):323-333
The purpose of this study is to develop new porous carbon materials by carbonising wood-based materials. One of the advantages of wood-based materials used as precursors for porous carbon materials is the simple and cost-effective production technique. Moreover, it is possible to make adjustments for a wide range of macro- and micro-structures by selecting different densities and particle sizes. Compared with solid wood, wood-based materials possess much greater homogeneity, isotropy and reproducible characteristics. Another great advantage is the fact that carbon materials can thus be produced from a renewable resource. A broad variety of specifically developed wood-based materials were carbonised to produce porous carbon materials for which characteristics such as density, yield, dimensional changes and surface area were determined. Light microscopy and mechanical testing were applied for further characterisation. The results showed how density and particle size affect the structure of the carbon materials; dimensional changes and mass loss are influenced by the carbonisation temperature, adhesive content and apparent density; increasing particle size decreases flexural strength and increasing apparent density or adhesive content raises flexural strength super-proportionally; and specific surface area increases with rising carbonisation temperatures. 相似文献
83.
MV Zbrun GC Zielinski HC Piscitelli C Descarga LA Urbani 《Journal of veterinary science (Suw?n-si, Korea)》2011,12(4):347-352
Infectious bovine keratoconjunctivitis (IBK) is an acute disease caused by Moraxella bovis (Mb). Several factors may predispose animals to an IBK outbreak; one commonly observed is infection with bovine herpes virus type 1 (BHV-1). The aim of this study was to investigate the dynamics of BHV-1 virus infection and its relation with clinical cases of IBK in weaned calves from a beef herd with a high prevalence of lesions caused by Mb. Sampling was carried out in six stages and included conjunctival swabs for isolating Mb as well as blood samples for identifying antibodies specific for BHV-1. A score for IBK lesions after observing each eye was determined. The findings of this study showed a high prevalence of BHV-1 virus infection (100% of animals were infected at the end of the trial); 67% of animals were culture-positive for Mb, but low rates of clinical IBK (19% of calves affected) were detected at the end of the trial. These results suggest that infection with BHV-1 did not predispose these animals to IBK, and that Mb infection produced clinical and subclinical disease in the absence of BHV-1 co-infection. 相似文献
84.
85.
Uwe Wegener 《Archives of Agronomy and Soil Science》2013,59(3-4):201-211
Der Beitrag behandelt die Entwicklung der Bergwiesenversuche im Harz von 1950 bis zum Jahr 2000. Während anfangs die Verbesserung der Erträge und des Futterwertes im Mittelpunkt stand, verlagerte sich in den siebziger Jahren der Schwerpunkt zu poly funktionalen Versuchen unter Einschluss des Erosionsschutzes, der Trinkwasserreinhaltung und der Sicherung der Artenvielfalt von Bergwiesen. Es konnte gezeigt werden, dass auf frischen Bergwiesen mit einer Düngergabe von 40–60 kg N/ha . a, 50 kg K/ha und 32 kg P/ha ein Ertrag von 50–70 dt/ha Heu bei gleichzeitiger Erhaltung der Artenvielfalt erreicht werden kann. Es gelingt auch die Aushagerung ehemals intensiv gedüngter Wiesenflächen. Diskutiert wird die heutige Situation des Berggrilnlandes. Nutzung und Schutz lassen sich derzeit nur mit Fördermitteln aufrecht erhalten. Aufwandarme Varianten der Wiesenpflege zur Erhaltung der Artenvielfalt werden dargestellt. Zur zukünftigen Sicherung des Kultur‐ und Schutzgutes “Bergwiese”; sind vielfältige Anstrengungen notwendig. Auf die zu erwartenden landschaftlichen Veränderungen, die Verminderung der Bergwiesenfläche zugunsten des Waldes, wird eingegangen. 相似文献
86.
Cristina López‐Fando Maria Teresa Pardo Fernandez Hans‐Richard Wegener 《Archives of Agronomy and Soil Science》2013,59(6):489-505
Im IOSDV Madrid wird seit 1984 die kombinierte Wirkung von Stallmist, Stroh, Zwischenfrucht und mineralischer N‐Düngung in der Fruchtfolge Sorghum‐Weizen‐Gerste auf einem semiariden Standort in der zentralspanischen Meseta auf einem Calcic Luvisol geprüft. Die Ergebnisse zeigen, dass die Witterungsbedingungen die Erträge wesentlich stärker beeinflussen als die Behandlungsvarianten. Durch die sehr geringen Niederschläge während der dritten Rotation waren die Gersten‐ und Weizenerträge unabhängig von der Düngung sehr niedrig, während unter optimalen Niederschlagsbedingungen in der ersten und zweiten Rotation die Weizen‐ und Gerstenerträge mit steigender N‐Düngung zunahmen und ihr Optimum bei der Stickstoffdüngungsstufe N3 aufwiesen; allerdings zeigte nur die Gerste eine Reaktion auf die gleichzeitige Anwendung organischer Dünger. Während der vierten Rotation wurden die Trockenmasse‐Erträge bei Weizen und Gerste durch organische Düngung bis zur Stufe N2 erhöht, während höhere Mineral‐N‐Gaben die Erträge negativ beeinflussten. Bei Sorghum traten, bedingt durch die extremen Niederschlagsbedingungen, erhebliche Schwierigkeiten auf, die sich in einem sehr niedrigen Korn‐Stroh‐Verhältnis widerspiegelten und keinerlei signifikanten Zusammenhang zu den Behandlungsvarianten erkennen liessen. 相似文献
87.
The Da-bu of Hanjae Lee mok (1471-1498) is known as an original masterpiece,which is predominantly documented in Korean tea books.He had always spared no effort to put Confucianists' theories and thoughts into practice during his 28-year career.Da-bu tea magnificently reflected his concepts of Confucianism in conjunction with tea-drinking activities.The main contents of Da-bu have included written authors,tea species and production,landscape of tea cultivation,tea plants and leaves,ways of tea-drinking and three-grade tea,tea song of seven cups,5 merits and 6 moralities of tea,benefits of tea-drinking,tea comprehension,etc.According to the views of contents,tea of Hanjae Leemok is the only partner with which we can share life and it can also be beneficial to healthy diets.Not only does it have become part of our daily life,but also be a medicine for our physical and mental disease.He composed the tea song of seven cups,which sufficiently expressed a real practice of the pursued ideal state of Confucianism and Taoism.He also promoted a drinking tea for health enrichment of Confucianists.According to the analytical results of Da-bu,Hanjae's tea has recognizably become the personally real practice of Confucianism and state.He had reached the enlightenment for the state of birth and death.After consuming tea,his body and mind immediately changed to the state of joys and wonderland,and also he illustrated that this feeling is not a one-off state,it always comes out whenever drinking.Therefore,based on Hanjae Lee mok,tea drinking is not only the regiment for healthy benefits,but also it is a training method," Dado in My Heart",for individuals to train their mind,body,and morality. 相似文献
88.
S. Typhimurium is one of the 2 most common salmonella serotypes causing human salmonellosis in Denmark. In order to illustrate the significance of different production animals as a source of infection, 1461 isolates were characterized by phage typing. The isolates originated from human patients and from cattle, pigs and poultry. By phage typing the isolates could be separated in 35 different phage types. Five types (10, 12, 66, 110 and 135) predominated and comprised 78.8% of the isolates. In humans, 57.3% of the isolates were phage type 12. This phage type was also predominant in pig herds and, to a lesser degree, in cattle. Phage types 110, 120, 135 and 193 constituted 86.5% of the poultry isolates while these phage types only made up 12.9% of the human isolates. The investigation showed that pigs are probably a major source of S. Typhimurium infection in humans in Denmark today. 相似文献
89.
Evaluation of thermally modified beech and spruce wood and their properties by FT-NIR spectroscopy 总被引:2,自引:2,他引:0
Helmut Bächle Bernhard Zimmer Elisabeth Windeisen Gerd Wegener 《Wood Science and Technology》2010,44(3):421-433
Quality assessment of thermally modified spruce (Picea abies (L.) Karst) and beech (Fagus sylvatica L.) wood and of the corresponding reference samples was carried out by means of non-destructive FT-NIR spectroscopic measurements
and PLS regression. Oven-dry and basic density as well as MOE and MOR determined by 3-point bending tests were evaluated.
The focus was put on specimens produced from material that had been thermally modified in an industrial scale kiln. Modelling
results range from poor to very good. The results of the spectra taken from the spruce samples resulted in better prediction
results than the spectra of the beech samples. This could be due to different proveniences or variation in the industrial
modification process. The results indicate that FT-NIR surface measurements of sound thermally modified wood samples could
be applied to evaluate several characteristics before and after the modification process. The method could be used for screening
during pre-sorting of thermally modified wood. 相似文献
90.
CHE Xian-da ZHANG Qing-gang QIAN Lin-yan ZHANG Xiao-hui GAO Rui-lan Beng HC Simon XL Xinmai J 《园艺学报》2010,26(2):222-226
AIM: To observe the effects of She Xiang Bao Xin Wan (SXBXW) of Chinese patent medicine on the proliferation of primary cultured vascular smooth muscle cells (VSMCs) from human umbilical artery and stimulated by endothelin-1 (ET-1) in vitro. METHODS: The proliferation cell models of primary cultured VSMCs were established by ET-1 stimulation. Six groups in the experiment were divided into control group; ET-1 group; ET-1+SXBXW 0.25 g/L; ET-1+SXBXW 0.5 g/L; ET-1+SXBXW 1.0 g/L and ET-1+SXBXW 2.0 g/L groups, respectively. The proliferation induced by ET-1 and the suppression mediated by SXBXW on VSMCs were measured by MTT method. The inhibitory rate and the cytotoxicity of SXBXW were detected by lactate dehydrogenase colorimetry and trypan blue exclusion tests. The effect of ET-1 and SXBXW on the cell proliferation cycle was analyzed by flow cytometry. RESULTS: Compared to control group, ET-1 significantly enhanced the proliferation of VSMCs (P<0.01). However, a certain dose of SXBXW inhibited effectively the proliferation of VSMCs induced by ET-1 in a dose-dependent manner (P<0.01). Meanwhile, SXBXW showed no influenced on both the number of living cells and the release of lactate dehydrogenase, although it inhibited the proliferation of VSMCs, indicating that SXBXW was no cytotoxicitic effect on VSMCs. ET-1 enhanced the proliferation of VSMCs by means of promoting the transition of the cell cycle from G1 phase to S phase. However SXBXW significantly inhibited the proliferation mediated by ET-1. CONCLUSION: SXBXW plays the role in suppressing VSMCs proliferation induced by ET-1. The mechanism may be involved in blocking the cell cycle from G1 phase into S phase. 相似文献