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Effects of dietary Clostridium butyricum and rumen protected fat on meat quality,oxidative stability,and chemical composition of finishing goats
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作者 Meimei Zhang Zhiyue Zhang +9 位作者 Xinlong Zhang Changming Lu Wenzhu Yang Xiaolai Xie Hangshu Xin Xiaotan Lu Mingbo Ni Xinyue Yang Xiaoyang Lv Peixin Jiao 《Journal of Animal Science and Biotechnology》 SCIE CAS CSCD 2024年第2期911-924,共14页
Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide ... Background Clostridium butyricum(CB)is a probiotic that can regulate intestinal microbial composition and improve meat quality.Rumen protected fat(RPF)has been shown to increase the dietary energy density and provide essential fatty acids.However,it is still unknown whether dietary supplementation with CB and RPF exerts beneficial effects on growth performance and nutritional value of goat meat.This study aimed to investigate the effects of dietary CB and RPF supplementation on growth performance,meat quality,oxidative stability,and meat nutritional value of finishing goats.Thirty-two goats(initial body weight,20.5±0.82 kg)were used in a completely randomized block design with a 2 RPF supplementation(0 vs.30 g/d)×2 CB supplementation(0 vs.1.0 g/d)factorial treatment arrangement.The experiment included a 14-d adaptation and 70-d data and sample collection period.The goats were fed a diet consisted of 400 g/kg peanut seedling and 600 g/kg corn-based concentrate(dry matter basis).Result Interaction between CB and RPF was rarely observed on the variables measured,except that shear force was reduced(P<0.05)by adding CB or RPF alone or their combination;the increased intramuscular fat(IMF)content with adding RPF was more pronounced(P<0.05)with CB than without CB addition.The pH24h(P=0.009),a*values(P=0.007),total antioxidant capacity(P=0.050),glutathione peroxidase activities(P=0.006),concentrations of 18:3(P<0.001),20:5(P=0.003)and total polyunsaturated fatty acids(P=0.048)were increased,whereas the L*values(P<0.001),shear force(P=0.050)and malondialdehyde content(P=0.044)were decreased by adding CB.Furthermore,CB supplementation increased essential amino acid(P=0.027),flavor amino acid(P=0.010)and total amino acid contents(P=0.024)as well as upregulated the expression of lipoprotein lipase(P=0.034)and peroxisome proliferator-activated receptorγ(PPARγ)(P=0.012),and downregulated the expression of stearoyl-CoA desaturase(SCD)(P=0.034).The RPF supplementation increased dry matter intake(P=0.005),averaged daily gain(trend,P=0.058),hot carcass weight(P=0.046),backfat thickness(P=0.006),concentrations of 16:0(P<0.001)and c9-18:1(P=0.002),and decreased the shear force(P<0.001),isoleucine(P=0.049)and lysine content(P=0.003)of meat.In addition,the expressions of acetyl-CoA carboxylase(P=0.003),fatty acid synthase(P=0.038),SCD(P<0.001)and PPARγ(P=0.022)were upregulated due to RPF supplementation,resulting in higher(P<0.001)content of IMF.Conclusions CB and RPF could be fed to goats for improving the growth performance,carcass traits and meat quality,and promote fat deposition by upregulating the expression of lipogenic genes of Longissimus thoracis muscle. 展开更多
关键词 chemical composition Clostridium butyricum Goats Meat quality Oxidative stability Rumen protected fat
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Effects of Different Exogenous Substances on Seed Germination of Isatis indigotica Under Drought Stress and Chemical Composition of Isatis indigotica leaves
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作者 Wang Hao Qin Jingjing +4 位作者 Shi Zhe Song Jiayao Ma Wuqiong Wang Huimin Cao Jinjun 《Journal of Northeast Agricultural University(English Edition)》 CAS 2024年第2期66-75,共10页
This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leavesand their efficacy in alleviating drought stress, and explore the methods of applying exogeno... This study was to investigate the effects of three exogenous substances on chemical constituents of Isatis indigotica leavesand their efficacy in alleviating drought stress, and explore the methods of applying exogenous substances to efficient cultivationof Isatis indigotica. Polyethylene glycol (PEG) was used to simulate drought stress to deal with seeds of Isatis indigotica at thegermination stage (concentration: 0, 10%, 15%, and 20%). Simultaneous operation of exogenous growth regulators [microbialinoculum (MI), γ-aminobutyric acid (GABA) and salicylic acid (SA)] and PEG were implemented in seeds of Isatis indigotica.The effects of drought stress and the mitigation of exogenous substances were observed by statistics of seed germination potential,germination rate, hypocotyl length, and radicle length of each treatment. The effects of exogenous substances on the content ofalkaloids, crude protein and free amino acids in the leaves of Isatis indigotica grown in a greenhouse were determined after sprayingexogenous substances on the plants. The differences of germination potential, germination rate, hypocotyl length, and radicle lengthamong 15% PEG stress treatment, 10% PEG stress treatment and the control were significant (P<0.05). According to the predesignedgermination standard, the seeds did not germinate under 20% PEG stress treatment. When the PEG concentration was 15%, the resultsof seed germination potential and germination rate after adding MI were significantly different from those under stress alone (P<0.05).When exposed to 10% PEG stress, the supplementation of GABA led to a notable increase in radicle length of Isatis indigotica seeds,showing significant differences compared to other three treatments. The application of MI and GABA under 15% PEG stress resultedin a significant increase in the radicle and hypocotyl length of Isatis indigotica seeds compared to other two treatments. The contentof the total alkaloids in leaves of Isatis indigotica was significantly increased after spraying GABA. Meanwhile, the contents of crudeprotein and the total free amino acids were kept constant after spraying exogenous substances. Application of MI and GABA couldalleviate drought stress of Isatis indigotica. The content of the total alkaloids in leaves of Isatis indigotica could significantly increaseafter spraying GABA. 展开更多
关键词 Isatis indigotica Fort. exogenous growth regulator drought stress chemical composition leaves of Isatis indigotica
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Effects of Biological Organic Fertilizer on Flue-cured Tobacco Chemical Composition 被引量:3
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作者 霍光 王镇 +1 位作者 孟贵星 化党领 《Agricultural Science & Technology》 CAS 2013年第8期1137-1141,1146,共6页
Through field experiment,special biological fertilizer and cake fertilizer were applied collectively to tobacco,and chemical compositions of Wanxi flue-cured tobacco leaves were researched.The results showed that the ... Through field experiment,special biological fertilizer and cake fertilizer were applied collectively to tobacco,and chemical compositions of Wanxi flue-cured tobacco leaves were researched.The results showed that the increase of biological organic fertilizer would significantly improve soil nutrient supplying capacity.Compared with conventional fertilization,the contents of reducing sugar,total sugar and starch in different parts of tobaccos which were applied with biological organic fertilizer were closer to standards of excellent tobacco.In the treatment,the ratio of reducing sugar and nicotine in tobacco was more suitable in middle and lower parts of the plant and the contents of total N,nicotine and chlorine in tobacco were lowered,improving tobacco quality. 展开更多
关键词 Biological organic fertilizer Soil Flue-cured tobacco chemical composition
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Study on Main Chemical Compositions of Rice Straw in Three Different Areas of Jiangsu Province 被引量:1
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作者 宋卫东 王教领 +3 位作者 王明友 吴今姬 李尚昆 王培雨 《Agricultural Science & Technology》 CAS 2016年第2期405-408,共4页
[Objective] The research was aimed to study the main chemical composi- tions of rice straw in the three different areas of Jiangsu Province. [Method] The cellulose, hemicellulose, lignin and crude ash of rice straw co... [Objective] The research was aimed to study the main chemical composi- tions of rice straw in the three different areas of Jiangsu Province. [Method] The cellulose, hemicellulose, lignin and crude ash of rice straw collected in Huaian, Changzhou and Zhenjiang of Jiangsu Province during 2011-2013 were determined. [Result] The change trends of cellulose and hemicellulose in three arrears in differ- ent years were consistent. The cellulose content increased after falling, and hemi- cellulose content presented declining tendency. The lignin content of rice straw fist rose then declined in Huaian and Changzhou in different years, while it presented the declining tendency in Zhenjiang. The ash content of rice straw changed little and was all less than 65% in the three areas in different years. And the chemical composition of rice straw changed significantly in different years. [Conclusion] The research could provide basis for high added-value use of crop straw. 展开更多
关键词 Rice straw Different years chemical composition Jiangsu Province
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Comparison on the Chemical Compositions in the K326 Tobacco from Different Tobacco-planting Areas of Yunnan Province 被引量:11
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作者 王岚 杨继周 +8 位作者 蒋美红 段俊杰 卢叶 敖金成 马彦清 李继飞 王涛 林楠 邓国宾 《Agricultural Science & Technology》 CAS 2012年第1期139-142,共4页
[Objective] To compare the regional differences of the conventional chemi- cal compositions in the K326 B2F tobacco from different tobacco-planting areas of Yunnan Province. [Methed] Continuous flow analyzer was used ... [Objective] To compare the regional differences of the conventional chemi- cal compositions in the K326 B2F tobacco from different tobacco-planting areas of Yunnan Province. [Methed] Continuous flow analyzer was used to detect the con- ventional chemical compositions, and SPSS 17.0 statistical package was used to conduct data statistical analysis and variance analysis. [Result] Significant differences were existed among most of the indicators for conventional chemical compositions of K326 tobacco in different areas: the differences of total sugar, reducing sugar and nicotine reached a high Significant level; potassium ion and total nitrogen differences reached a significant level, while there was no significant difference in chlorine ion. Most of the conventional chemical compositions in K326 B2F tabacco planted in Yuxi region and those planted in Qujing, Dali and Chuxiong were significantly different. The total sugar, reducing sugar and nicotine contents of tobacco planted in eastern Yunnan, central Yunnan and western Yunnan were significantly different; while the conventional chemical compositions contents in the tobacco planted in Chuxiong and Dali, which all belong to western Yunnan, showed no obvious significant difference, indicating different ecological environments in large area had a great impact on the tobacco of Yunnan Province. [Conclusion] It revealed the regional characteristics of the conventional chemical compositions in K326 flue-cured tobacco leaves from Yunnan Province, providing references for the cigarette blending and production of high-quality tobacco with characteristics. 展开更多
关键词 K326 B2F Conventional chemical compositions DIFFERENCE
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A study of the chemical composition and transport of marine aerosols over the ocean near China 被引量:1
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作者 Zhang Ni, Zhou Mingyu, Lu Naiping, F. P. Parungo, Wen Yupu, Yang Shaojing, Yang Yinan and Chen Binru National Research Center for Marine Environmental Forecasts, State Oceanic Administration, Beijing, ChinaNational Oceanic and Atmospheric Administration, Environmental Research Laboratories, Air Resources Laboratory, Boulder,CO, U.S. A.Academy of Meteorological Sciences, State Meteorological Administration, Beijing, ChinaInstitute of High Energy Physics, Academia Sinica, Beijing, China 《Acta Oceanologica Sinica》 SCIE CAS CSCD 1991年第3期407-422,共16页
In this paper the authors cite the aerosol samples collected with a KA-200 Anderson cascade Impactor and a KB-120 sampler during the first cruise of the Kuroshio investigation operated by the People's Republic of ... In this paper the authors cite the aerosol samples collected with a KA-200 Anderson cascade Impactor and a KB-120 sampler during the first cruise of the Kuroshio investigation operated by the People's Republic of China and Japan cooperative program, from July 23 to August 21, 1987. The concentration size distributions and composition of marine aerosols over the Kuroshio area are analyzed. Neutron activation analysis is used to determine the elemental composition of the aerosols. The authors also discuss some characteristics of marine aerosols relating to long-range transport of crustal and anthropogenic elements from the continent to the remote ocean. Analytical results indicate that elements Al, Fe, Sc and Sb over this area are obviously influenced by the continent of Asia, and the size distributions are changed after long-range transport. The concentration of large particles increase. The concentrations of the elements C1 and Na are closely related to ocean conditions; the source of the elements Cl and Na is mainly the ocean. Besides coal combustion, the ocean is also a very important source for the element Se. The amount of Se is related to the distribution of marine life. 展开更多
关键词 Sb A study of the chemical composition and transport of marine aerosols over the ocean near China OVER
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Phase-field study for effect of chemical composition on pre-precipitation process of γ′ phase in Ni-Al-Ti alloy
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作者 孙远洋 赵宇宏 +2 位作者 侯华 郑晓娟 郭慧俊 《Journal of Measurement Science and Instrumentation》 CAS CSCD 2017年第2期178-184,共7页
The pre-precipitation processes of γ' phase in Ni-Al-Ti alloy with different chemical compositions are investigated by microscopic phase-field dynamics model. The simulation results show that the early precip... The pre-precipitation processes of γ' phase in Ni-Al-Ti alloy with different chemical compositions are investigated by microscopic phase-field dynamics model. The simulation results show that the early precipitated phase with L10 structure is formed before the formation of γ' phase. With the increase of Al content, the composition of precipitated phase is transformed from the co-existence of γ' phase and material phase into single y phase. Furthermore, excessive Al content can stimulate the production of γ' phase, and the conversion time from L10 phase to L12 phase will lag behind other samples with lower Al con-tent. By analyzing the occupation probability of Ti, it can be found that the solid solution strengthening effect of Ti is reduced with the increase of Al component. 展开更多
关键词 chemical composition L10 phase microscopic phase field model volume fraction
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Wood Density of Ten Native Trees and Shrubs and Its Possible Relation with a Few Wood Chemical Compositions
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作者 Ratikanta Maiti Humberto Gonzalez Rodriguez Aruna Kumari 《American Journal of Plant Sciences》 2016年第8期1192-1197,共6页
The present study was undertaken in Forest Science Faculty, Universidad de Nuevo Leon, Mexico on variability of Wood density and its possible relation to few wood chemical composition and wood fiber cell structure ana... The present study was undertaken in Forest Science Faculty, Universidad de Nuevo Leon, Mexico on variability of Wood density and its possible relation to few wood chemical composition and wood fiber cell structure anatomy. The results reveal that among 10 specie studied, there exist a large variation in wood density (0.51 to 1.09), and few wood chemical composition such % carbón (37.14 to 44.07), nitrogen (9.18 to 19.22), sulphur (31.45 to 33/82), lignin (15/28 to 24.35), hemicellulose (19.94 to 27.36%), and % cellulose (33.69 to 45.92). In general, though there was no clear relationship between wood density and other chemical composition of wood. It was observed that the species having moderate to high wood density contained >40% carbón, >30% sulphur and >40% cellulose and more or less 20% lignin. It seems that carbón, sulphur, cellulose and lignin content contribute to greater density. The wood fiber cell with wall lignification seems to be related to higher wood density. 展开更多
关键词 Wood Density Wood chemical composition CELLULOSE LIGNIN Carbón Concentration Variability
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Chromatographic Analysis of Chemical Composition of the Genus Rhododendron Plants Growing on the Mountain of Evota (South Yakutia)
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作者 Zaytseva Nataha Vladlmlrovna Pogulyaeva Irina Alexandrovna 《Journal of Chemistry and Chemical Engineering》 2014年第5期516-523,共8页
The data on chemical compounds of three Rododendron species (Rh. adamsii Rehd., Rh. aureum Georgi. and Rh. lapponicum subsp, parvifolium (Adams) T. Yamaz.) from the mountain of Evota top in South Yakutia are shown... The data on chemical compounds of three Rododendron species (Rh. adamsii Rehd., Rh. aureum Georgi. and Rh. lapponicum subsp, parvifolium (Adams) T. Yamaz.) from the mountain of Evota top in South Yakutia are shown. Extracts of these plants was analyzed by method of planar chromatography in thin layers using different specific detectors to exposure of some groups of biologically active matters. During the researches, it was established that polyphenol compounds of different degree of condensment prevail in rhododendron composition; catechines, flavonoids, coumarins, saponins, essential oils, phenol carboxylic acids and arbutin are present too. Due to detected features, all the researched species of rhododendrons are perspective for practical using in food industry and as adaptogenes for maintenance of people health in the conditions of north. 展开更多
关键词 South Yakutia the chemical composition of Rhododendron adaptation to high-altitude conditions planarchromatography.
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A Comparison Analysis of Chemical Composition of Aerosols in the Dust and Non-Dust Periods in Beijing 被引量:12
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作者 张仁健 徐永福 韩志伟 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第2期300-305,共6页
Dust events occurred frequently in Beijing in recent years. In this work, 120 aerosol samples were collected in two typical dust events (21-22 March and 15 May) and a non-dust period in Beijing from March to May 2001.... Dust events occurred frequently in Beijing in recent years. In this work, 120 aerosol samples were collected in two typical dust events (21-22 March and 15 May) and a non-dust period in Beijing from March to May 2001. Samples were analyzed for major elemental components by the Proton Induced X-ray Emission (PIXE) method. Results show that the enrichment factors of crustal elements such as Mg, Al, and Ti had little differences between the dust period and the non-dust period in Beijing, while the enrichment factors of other elements that have a relation to anthropogenic emissions were very low during the dust period. The results derived by using multivariate factor analysis from the observation data show that the sources such as soil dust, industry, and fuel combustion were among the major contributors to the particles in Beijing. 展开更多
关键词 DUST AEROSOL chemical composition Proton Induced X-ray Emission method
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Liquefaction and Product Identification of Main Chemical Compositions of Wood in Phenol 被引量:14
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作者 Zhang Qiu-hui Zhao Guang-jie Jie Shu-jun 《Forestry Studies in China》 CAS 2005年第2期31-37,共7页
To clarify liquefaction ratios and their construction variations of the main chemical compositions of wood in phenol using phosphoric acid as a catalyst, the chemical ingredients of wood such as holocellulose, cellulo... To clarify liquefaction ratios and their construction variations of the main chemical compositions of wood in phenol using phosphoric acid as a catalyst, the chemical ingredients of wood such as holocellulose, cellulose and lignin, were measured and extracted according to GB methods. With Fourier transform infrared (FTIR), the product identification of reactant before and after liquefaction in phenol was investigated. The molecular weights and their distributions of the liquefaction results (acetone soluble parts) were studied by gel permeation chromatography (GPC). Results show that the molecular weights and their distributions of poplar and Chinese fir are almost the same. In poplar, the distribution of cellulose is the largest, and that ofholocellulose the smallest after liquefaction. For Chinese fir, the distribution of holocellulose is the largest, and that of cellulose the smallest. After liquefaction of poplar cellulose, the change bands of FTIR spectrum observed below 1 600 cm^-1, can be attributed to new substitute groups. The same is true for poplar lignin. For Chinese fir, the spectra of liquefaction results of all chemical compositions differ from that of wood meal. This reveals the more activity groups were produced because of the reactions between Chinese fir and phenol. The research shows that the liquefaction ratios of poplar decrease in the following order: holocellulose 〉 lignin 〉 cellulose, and those of Chinese fir in the order: lignin 〉 cellulose 〉 holocellulose. 展开更多
关键词 wood liquefaction in phenol residue ratio chemical composition FTIR GPC
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Effect of Cellulase and Lactic Acid Bacteria on Fermentation Quality and Chemical Composition of Wheat Straw Silage 被引量:16
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作者 Kuikui Ni Yanping Wang +1 位作者 Huili Pang Yimin Cai 《American Journal of Plant Sciences》 2014年第13期1877-1884,共8页
The object of this study was to determine the effect of cellulase and lactic acid bacteria (LAB) on fermentation quality and chemical composition of wheat straw silage. Silages were prepared using a small-scale fermen... The object of this study was to determine the effect of cellulase and lactic acid bacteria (LAB) on fermentation quality and chemical composition of wheat straw silage. Silages were prepared using a small-scale fermentation system and the moisture level was adjusted to 60% of fresh matter (FM) with deionized water. Treatments were designed as: control silage without additives, LAB inoculant Lactobacillus casei Z3-1 (1.0 × 106 cfu·g-1 of FM), commercial inoculant L. plantarum FG 1 (1.0 × 106 cfu·g-1 of FM), Z3-1 + cellulase and FG 1 + cellulase. The neutral detergent fiber (NDF), acid detergent fiber (ADF) and crude protein (CP) contents of the wheat straw prior to ensiling were 76.93%, 48.52% and 4.63% of dry matter (DM), respectively. After 30 days of fermentation, the silages treated with LAB and LAB + cellulase had a lower (P < 0.05) pH and higher (P < 0.05) lactic acid content than the control, and the coliform bacteria, yeast and mold were inhibited at the early stage of fermentation. Besides, silages treated with cellulase had lower (P < 0.05) values of ADF and NDF than the control. The results confirmed that the addition of cellulase and LAB contributed to improving the fermentation quality of wheat straw silage. 展开更多
关键词 CELLULASE chemical composition LACTIC Acid BACTERIA SILAGE FERMENTATION Wheat STRAW
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The Impact of the South Asia High Bimodality on the Chemical Composition of the Upper Troposphere and Lower Stratosphere 被引量:14
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作者 YAN Ren-Chang BIAN Jian-Chun FAN Qiu-Jun 《Atmospheric and Oceanic Science Letters》 2011年第4期229-234,共6页
The South Asia High (SAH) is the dominant feature of the circulation in the upper troposphere and lower stratosphere (UTLS) during the boreal summer, and the upper tropospheric anticyclonic circulation extends int... The South Asia High (SAH) is the dominant feature of the circulation in the upper troposphere and lower stratosphere (UTLS) during the boreal summer, and the upper tropospheric anticyclonic circulation extends into the lower stratosphere. The preferred locations of the center of the SAH occur in two different regions, and the center can be located over the Iranian Plateau or over the Tibetan Plateau. This bimodality has an impact on the distribution of chemical constituents in the UTLS region. We analyzed water vapor (H20), carbon monoxide (CO), and ozone (03) data derived from the Aura Microwave Limb Sounder (MLS) and total column ozone data from the Ozone Monitoring Instrument (OMI). For the Iranian Plateau mode of the SAH, the tropospheric tracers exhibited a positive anomaly over the Iranian Plateau and a negative anomaly over the Tibetan Plateau, whereas the stratospheric tracer exhibited a negative and a positive anomaly over the Iranian Plateau and the Tibetan Plateau, respectively. For the Tibetan Plateau mode, however, the distribution of the anomaly was the reverse of that found for the chemical species in the UTLS region. Furthermore, the locations of the extrema within the anomaly seemed to differ across chemical species. The anomaly extrema for H20 occurred in the vicinity of the SAH ridgeline, whereas CO and O3 exhibited a northward shift of 4-8 degrees. These impacts of the variation in the SAH on the chemical constitutes in the UTLS region can be attributed in part to the dynamical structure delineated by the tropopause field and the temperature field at 100 hPa. 展开更多
关键词 SAH UTLS chemical composition BIMODALITY
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Optimization model coupling both chemical compositions and high-temperature characteristics of sintering materials for sintering burden 被引量:4
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作者 Ke-jiang Li Jian-liang Zhang +3 位作者 Zheng-jian Liu Bu-xin Su Ling-tan Kong Tian-jun Yang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2014年第3期216-224,共9页
We developed a mathematical optimization model coupling chemical compositions and high-temperature characteristics of sintering materials, targeting the best quality and lowest cost. The simplex algorithm was adopted ... We developed a mathematical optimization model coupling chemical compositions and high-temperature characteristics of sintering materials, targeting the best quality and lowest cost. The simplex algorithm was adopted to solve this model. Four kinds of imported iron ores, two kinds of Chinese iron ore concentrates, and two kinds of fluxes were selected to verify both the model and the algorithm. The results confirmed the possibility of considering both chemical compositions and high-temperature characteristics of iron ores in the optimization model. This model provides a technical roadmap to obtain a precise mathematical correlation between the lowest cost and the grade of iron in sinters based on the condition of given raw materials, which can provide a reference to adjust the grade of iron in the sintering process for enterprise. 展开更多
关键词 SINTERING BURDEN OPTIMIZATION simplex algorithm chemical composition high temperature properies
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Antimycobacterial natural products from Moroccan medicinal plants: Chemical composition, bacteriostatic and bactericidal profile of Thymus satureioides and Mentha pulegium essential oils 被引量:3
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作者 Marwa Chraibi Abdellah Farah +3 位作者 Sara Lebrazi Oumaima El Amine Mohammed Iraqui Houssaini Kawtar Fikri-Benbrahim 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2016年第10期836-840,共5页
Objective: To evaluate the susceptibility of Mycobacterium aurum and Mycobacterium smegmatis in vitro to the essential oils obtained from two medicinal plants: Thymus satureioides(T. satureioides) and Mentha pulegium(... Objective: To evaluate the susceptibility of Mycobacterium aurum and Mycobacterium smegmatis in vitro to the essential oils obtained from two medicinal plants: Thymus satureioides(T. satureioides) and Mentha pulegium(M. pulegium), and to study their chemical composition.Methods: The aerial parts of T. satureioides and M. pulegium(leaves and stems) were hydro-distillated using a Clevenger-type apparatus and essential oils were analyzed and identified by gas chromatography-mass spectrometry. Antimycobacterial screening of essential oils was performed on the basis of the inhibition zone diameter by disc diffusion method against two mycobacterial strains whereas the minimal inhibitory concentration and minimal bactericidal concentration were determined by using the micro-dilution method.Results: Chemical analysis of their aerial part's essential oils gave as major compounds,borneol(34.26%), carvacrol(31.21%) and thymol(3.71%) for T. satureioides and R(+)-pulegone(75.48%), carvone(6.66%) and dihydrocarvone(4.64%) for M. pulegium.Thereafter their antimycobacterial effect evaluation, using the micro-dilution method,indicated that minimal inhibitory concentration values of T. satureioides essential oil ranged from 0.062% to 0.015%(v/v) and from 0.125% to 0.031%(v/v) for M. pulegium respectively against Mycobacterium aurum and Mycobacterium smegmatis.Conclusions: It is clearly evident from the results obtained that the Moroccan medicinal plants have great potential to be used as anti-tuberculosis agents. These findings may help scientists to undertake several research projects to discover useful natural product as new anti-tuberculosis drug. 展开更多
关键词 THYMUS satureioides MENTHA pulegium Essential oil chemical composition ANTIMYCOBACTERIAL activity
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Effect of harvest time on the chemical composition and antioxidant capacity of Gannan navel orange(Citrus sinensis L. Osbeck 'Newhall')juice 被引量:8
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作者 ZHANG Jun ZHANG Jing-yi +6 位作者 SHAN You-xia GUO Can HE Lian ZHANG Lin-yan LING Wei LIANG Yan ZHONG Ba-lian 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2022年第1期261-272,共12页
The present study investigates the chemical composition and antioxidant capacity of juice from the Gannan navel orange, which is harvested at one-to two-week intervals during the ripening period. The total soluble sol... The present study investigates the chemical composition and antioxidant capacity of juice from the Gannan navel orange, which is harvested at one-to two-week intervals during the ripening period. The total soluble solid(TSS), total polyphenol content(TPC), total flavonoid content(TFC), sucrose and hesperidin contents gradually increase with the ripening of the fruit, followed by slight declines at the late maturity stage. Contrary to these observations, the contents of titratable acid(TA), vitamin C(Vc), and limonin trend downward throughout the ripening period. However, the contents of fructose, glucose, and narirutin fluctuate throughout the harvest time. Three in vitro antioxidant assays consistently indicate that the harvest time exerts no significant influence(P>0.01) on the antioxidant capacity. Furthermore, principal component analysis(PCA) and Pearson’s correlation test are performed to provide an overview of the complete dataset.This study provides valuable information for evaluating the fruit quality and determining when to harvest the fruit in order to meet the preferences of consumers. Meanwhile, our observations suggest that the fruits subjected to juice processing should be harvested at the late maturity stage to alleviate the "delayed bitterness" problem without compromising the antioxidant capacity and the flavonoid content in the juice. 展开更多
关键词 navel orange ANTIOXIDANT harvest time chemical composition
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Synthesis of steel slag ceramics: chemical composition and crystalline phases of raw materials 被引量:3
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作者 Li-hua Zhao Wei Wei +2 位作者 Hao Bai Xu Zhang Da-qiang Cang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2015年第3期325-333,共9页
Two types of porcelain tiles with steel slag as the main raw material (steel slag ceramics) were synthesized based on the CaO-A1203-SiO2 and CaO--MgO-SiO2 systems, and their bending strengths up to 53.47 MPa and 99.... Two types of porcelain tiles with steel slag as the main raw material (steel slag ceramics) were synthesized based on the CaO-A1203-SiO2 and CaO--MgO-SiO2 systems, and their bending strengths up to 53.47 MPa and 99.84 MPa, respectively, were obtained. The presence of anorthite, a-quartz, magnetite, and pyroxene crystals (augite and diopside) in the steel slag ceramics were very different from the composition of traditional ceramics. X-ray diffraction (XRD) and electron probe X-ray microanalysis (EPMA) results illustrated that the addition of steel slag reduced the temperature of extensive liquid generation and further decreased the firing temperature. The considerable contents of glass-modifying oxide liquids with rather low viscosities at high temperature in the steel slag ceramic adobes promoted element diffusion and crystallization. The results of this study demonstrated a new approach for extensive and effective recycling of steel slag. 展开更多
关键词 ceramic materials SYNTHESIS steel slag chemical composition crystalline phases solid waste recycling
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Influence of chemical composition on corrosion resistance of AZ91D magnesium alloy ingots 被引量:3
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作者 林高用 彭大暑 张 辉 《中国有色金属学报》 EI CAS CSCD 北大核心 2001年第z1期79-82,共4页
The influence of chemical composition on corrosion resistance of AZ91D magnesium alloys ingots has been investigated. Mass loss method was applied to evaluate the corrosion resistance of AZ91D alloys and the data were... The influence of chemical composition on corrosion resistance of AZ91D magnesium alloys ingots has been investigated. Mass loss method was applied to evaluate the corrosion resistance of AZ91D alloys and the data were analyzed by multiple regression. The results show that the corrosion resistance of this alloy can be improved by increasing Al, Zn and Mn in a certain degree, and will drop with increasing Si and heavy metals (Fe, Cu, Ni). It is found that ingots received from company F should be listed into unusable materials in terms of the corrosion resistance, while among the five suppliers, the only local company E supplied excellent AZ91D magnesium alloy ingots with the best corrosion resistance. 展开更多
关键词 AZ91D magnesium alloy chemical composition property of corrosion resistance corrosion rate
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The Joint Use of Electronic Nose and Electronic Tongue for the Evaluation of the Sensorial Properties of Green and Black Tea Infusions as Related to Their Chemical Composition 被引量:4
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作者 Susanna Buratti Antonella Casiraghi +1 位作者 Paola Minghetti Gabriella Giovanelli 《Food and Nutrition Sciences》 2013年第6期605-615,共11页
The objectives of the present study were to determine the effects of the brewing method on the amount of the major catechins, methylxanthines, total polyphenols and antioxidant capacity in green and black teas, and to... The objectives of the present study were to determine the effects of the brewing method on the amount of the major catechins, methylxanthines, total polyphenols and antioxidant capacity in green and black teas, and to correlate the chemical composition of tea infusions to their sensorial properties by the combined use of the electronic nose and tongue. For this purpose, tea infusions were prepared from 7 green teas and 6 black teas using different extraction times (3 - 5 and 10 min). The extraction of total polyphenols and catechins was increased by prolonging the infusion time from 3 - 5 to 10 min, while the caffeine amounts did not increase. The antioxidant activity of teas was well correlated with polyphenol content. Electronic tongue and electronic nose were able to discriminate green teas from black teas on the basis of their sensorial properties. Considering the taste, green teas were characterized by astringency and aftertaste-astringency and this sensation was increased by prolonging the infusion time;black teas were perceived as more bitter, sour, salty and the extraction time affected the astringent sensation. The aroma of green and black teas was discriminated by specific sensors and the increase of the extraction time produced more richly flavoured infusions. This work adds information about correlation between sensorial properties, antioxidant capacity and chemical composition of green and black teas. 展开更多
关键词 Green TEA Black TEA ELECTRONIC NOSE ELECTRONIC TONGUE chemical composition ANTIOXIDANT Activity
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Advances in Researches on Chemical Composition and Functions of Hemerocallis Plants 被引量:3
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作者 Yan WANG Teng XU +5 位作者 Bei FAN Lijing ZHANG Cong LU Donghui WANG Xinmin LIU Fengzhong WANG 《Medicinal Plant》 CAS 2018年第2期16-21,共6页
The genus Hemerocallis is a kind of perennial herbaceous plants of Liliaceae and consists of about 15 species in the world,11 of which can be found in China. Some species of Hemerocallis are widely cultivated for medi... The genus Hemerocallis is a kind of perennial herbaceous plants of Liliaceae and consists of about 15 species in the world,11 of which can be found in China. Some species of Hemerocallis are widely cultivated for medicinal,edible and ornamental application. Considerable progress had been made in researches on chemical composition and functions of Hemerocallis plants. Previous phytochemical studies on Hemerocallis plants have demonstrated the presence of flavonoids,anthraquinones,alkaloids,terpenoids,triterpenes and triterpenoid saponins,caffeoylquinic acid derivatives,naphthalene glycosides,steroid and steroidal saponins,phenylethanoid glycosides,and lignans. Functional activities of Hemerocallis plants are mainly manifested in sedative hypnotic,antidepressant,antioxidant,anti-tumor,hepatoprotective,antibacterial and insecticidal activities. Chemical composition of Hemerocallis plants is various,and structural type is rich,and has a variety of significant functional activities,so it is worth further study. 展开更多
关键词 HEMEROCALLIS Hemerocallis citrina Baroni chemical composition FUNCTIONS FLAVONOIDS Sedative hypnotic ANTIDEPRESSANT
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