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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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Chemical Composition of Pineapple Press Residues (Ananas comosus) and Effect on Growth Performance of Rabbit (Oryctolagus cuniculus)
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作者 Bertine Marie Noël Noumbissi Emile Miegoue +4 位作者 Nathaniel Arnaud Jordy Nguema Nathalie Ngouopou Mweugang Langston Wilfried Edie Nounamo Cedric Nyah Kwayep Fernand Tendonkeng 《Open Journal of Animal Sciences》 2024年第4期321-335,共15页
With a view to improving rabbit production performance, a trial on the chemical composition of pineapple press residue (Ananas comosus) and the effect of its incorporation in the ration on rabbit growth performance (O... With a view to improving rabbit production performance, a trial on the chemical composition of pineapple press residue (Ananas comosus) and the effect of its incorporation in the ration on rabbit growth performance (Oryctolagus cuniculus) was carried out at the KUATE Cunicole Farm in Bandjoun, in Western Cameroon. To do this, 36 rabbits of the local breed, aged 53 days with an average weight of 1337 ± 119 g were distributed and randomly assigned to 3 experimental rations corresponding respectively to treatments or batches T0, T1 and T2. The animals in treatment T0 received a ration containing no pineapple press residue, while those in treatments T1 and T2 received a ration containing 20% and 40% pineapple press residue, respectively. These residues were dried and ground for chemical composition analysis. The feed served as well as refusals from the previous day were weighed each morning to assess feed intake. The animals were weighed every 7 days to assess weight performance. At the end of the trial which lasted 7 weeks, the animals were fasted for 24 hours, then sacrificed to evaluate carcass characteristics and the relative weights of some digestive organs. The results of this study showed that pineapple press residues had a high crude fiber content (19.2%) and energy (2500 Kcal/kg DM). Their incorporation had no significant effect on feed intake and feed conversion ratio. The average live weight, weight gain and average daily weight gain of the animals receiving the ration with 20% inclusion of pineapple press residue were comparable to those of the control group and significantly higher than those of animals fed with 40% inclusion of pineapple residue. The highest carcass yields were obtained with rabbits fed 20% pineapple press residue in their ration. The cost of feed for the production of a kilogram live weight of rabbit tends to decrease with the ration incorporated with 20% pineapple press residue. Pineapple press residues constitute a by-product that can be recycled and their incorporation at 20% can increase rabbit growth performance and reduce production costs. 展开更多
关键词 chemical composition Growth Pineapple Press Residue Production Cost RABBIT
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Chemical composition and pharmacological activities of Atractylodes lancea:A review
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作者 Shuo Wanga Yunpeng Yang +3 位作者 Yibo Wang Wenhan Wang Meng Zhang Yu Chen 《Asian Journal of Traditional Medicines》 2024年第3期159-171,共13页
Atractylodes lancea(called Cangzhu in China)is a medicinal plant that has long been used as tonic agent in various ethno-medical systems in East Asia,especially in China,for the treatment of gastrointestinal dysfuncti... Atractylodes lancea(called Cangzhu in China)is a medicinal plant that has long been used as tonic agent in various ethno-medical systems in East Asia,especially in China,for the treatment of gastrointestinal dysfunction,cancer,osteoporosis,obesity and fetal irritability.We used the TCMSP database to search for the main active ingredients and traditional Chinese medicine targets of Atractylodes macrocephala.There are a total of 38 related articles,of which 27 are closely related to chemical composition and activity.This study reviews the chemical components and pharmacological effects of A.lancea,aiming to provide reference for its further research and development. 展开更多
关键词 Atractylodes lancea chemical composition pharmacological activities
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Chemical composition and biological activity of Houttuynia cordata
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作者 Yibo Wang Yunpeng Yang +3 位作者 Xinyao Wang Wenhan Wang Luming Pan Yu Chen 《Asian Journal of Traditional Medicines》 2024年第4期223-234,共12页
Houttuynia cordata is an important traditional Chinese medicine.It is widely used for clearing heat and detoxification,reducing swelling and treating sores,diuresis and dehumidification.It is also used to treat lung c... Houttuynia cordata is an important traditional Chinese medicine.It is widely used for clearing heat and detoxification,reducing swelling and treating sores,diuresis and dehumidification.It is also used to treat lung carbuncles,ulcers,hemorrhoids,rectal bleeding,spleen and stomach heat,which are caused by excess heat,heat toxicity,dampness,and disease heat.Modern pharmacological experiments have shown that H.cordata has antibacterial,antiviral,immune enhancing,diuretic and other effects.This article reviews the chemical components and biological activities of H.cordata to provide reference for clinical application. 展开更多
关键词 Houttuynia cordata chemical composition biological activity
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Chemical composition and pharmacological activities of the Phellodendron chinense Schneid
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作者 Yi′an Shi Yunpeng Yang +3 位作者 Wenhan Wang Yibo Wan Yao Zhao Yu Chen 《Asian Journal of Traditional Medicines》 2024年第5期285-298,共14页
Phellodendron chinense Schneid(P.chinense),as a traditional Chinese medicine,is commonly used in clinical practice.It has the effects of drying dampness,clearing heat,detoxifying,purging fire,and reducing swelling.Its... Phellodendron chinense Schneid(P.chinense),as a traditional Chinese medicine,is commonly used in clinical practice.It has the effects of drying dampness,clearing heat,detoxifying,purging fire,and reducing swelling.Its main chemical components are flavonoids and alkaloids,which have various pharmacological effects such as lowering blood sugar,lowering blood pressure and immunosuppression.With the continuous development of modern science and technology,the research on P.chinense Schneid has increased.This study reviews the chemical components and pharmacological effects of P.chinense Schneid,and provides reference for its further research and development. 展开更多
关键词 Phellodendron chinense Schneid chemical composition pharmacological activity
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Chemical compositions and biological activities of Flos lonicerae 被引量:1
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作者 Yi’an Shi Luming Pan +3 位作者 Luyan Yang Jing Sun Meng Zhang Yu Chen 《Asian Journal of Traditional Medicines》 CAS 2023年第2期60-68,共9页
Flos lonicerae is the dry flower bud of Lonicera japonica Thunb,and it is a very important Chinese herbal medicine in China.In ancient times,it was widely used to treat the exopathogenic wind-heat,epidemic febrile dis... Flos lonicerae is the dry flower bud of Lonicera japonica Thunb,and it is a very important Chinese herbal medicine in China.In ancient times,it was widely used to treat the exopathogenic wind-heat,epidemic febrile diseases,sores,carbuncles and some infectious diseases.Modern pharmacological research has indicated that it has anti-inflammatory,anti-bacterial,anti-viral and anti-oxidation activities.This paper reviews the chemical compositions and biological activities of Flos lonicerae in order to provide reference for its application in clinical practice in the future. 展开更多
关键词 Flos lonicerae chemical composition biological activity
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Comparative advantages of chemical compositions of specific edible vegetable oils
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作者 Li Xue Ruinan Yang +4 位作者 Xuefang Wang Fei Ma Li Yu Liangxiao Zhang Peiwu Li 《Oil Crop Science》 CSCD 2023年第1期1-6,共6页
As important supplementary to major edible oils, comparative chemical advantages of minor edible oils decidetheir development and usage. In this study, chemical composition of 13 kinds of specific edible vegetable oil... As important supplementary to major edible oils, comparative chemical advantages of minor edible oils decidetheir development and usage. In this study, chemical composition of 13 kinds of specific edible vegetable oilswere investigated. The comparative advantages of chemical compositions of these edible oils were obtained asfollows: (1) camellia, tiger nut and almond oil were rich in oleic acid, the contents of which accounted for79.43%, 69.16% and 66.26%, respectively;(2) safflower oil contained the highest content of linoleic acid(76.69%), followed by grape seed (66.85%) and walnut oil (57.30%);(3) perilla seed, siritch, peony seed andherbaceous peony seed oil were rich in α-linolenic acid (59.61%, 43.74%, 40.83% and 30.84%, respectively);(4)the total phytosterol contents of these oils ranged from 91.46 mg/100 g (camellia oil) to 506.46 mg/100 g (siritchoil);and (5) The best source of tocopherols was sacha inchi oil (122.74 mg/100 g), followed by perilla seed oil(55.89 mg/100 g), peony seed oil (53.73 mg/100 g) and herbaceous peony seed oil (47.17 mg/100 g). Thecomparative advantages of these specific edible oils indicated that they possess the high potential nutritionalvalues and health care functions. 展开更多
关键词 Comparative advantages Fatty acid composition Phytosterols Tocopherols Specific vegetable oils chemical composition
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Chemical Composition of Sphyraena barracuda with Different Area, Size and Season, in Sudanese Red Sea Coast
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作者 Hala Gindeel A. Ahmadoon Abdall N. Elawad +1 位作者 Alamin M. Alamin Adam A. Babiker 《Food and Nutrition Sciences》 CAS 2023年第5期415-420,共6页
This study aims to determine the effect of area, size and season on chemical composition of Sphyraena barracuda from Sudanese Red Sea Coast. A total of 180 fish samples were collected from Port Sudan and Sawakin fishi... This study aims to determine the effect of area, size and season on chemical composition of Sphyraena barracuda from Sudanese Red Sea Coast. A total of 180 fish samples were collected from Port Sudan and Sawakin fishing sites during the winter and summer of 2020-2021. The fishes sample ranged between (30 - 50) cm in total length and (250 - 1000) gm in body weight of small size, and ranged between (60 - 90) cm in total length and (1250 - 250) gm in body weight for large size. Fish flesh was subject to gross chemical analysis. Moisture, protein, fat, ash, acidity and pH were determined. The results indicated a significant effect by area, season and size. The different areas had a significant effect on crude protein and ash;higher parameter value is found in Sawakin. Higher chemical parameters were showed in winter than in summer. Also, size had a significant effect in all parameters (except moisture), fat and ash were high in large size. The study has concluded that the large size fishes of S. barracuda with high nutritional value when caught in winter from the southern region of Sawakin. 展开更多
关键词 Area chemical composition Season and Size
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Advances in the Study of Chemical Composition and Biological Activities of Aloe Vera Flowers
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作者 Yan Yongtao Li Xiaomin Yu Xiaoyi 《China Detergent & Cosmetics》 CAS 2023年第3期63-68,共6页
This review summarizes the main chemical composition of Aloe vera flowers and introduces their antioxidant,anti-aging,skin whitening,skin moisturizing,anti-skin irritation,and anti-skin allergy effects.Suggestions for... This review summarizes the main chemical composition of Aloe vera flowers and introduces their antioxidant,anti-aging,skin whitening,skin moisturizing,anti-skin irritation,and anti-skin allergy effects.Suggestions for the application of Aloe v.flowers in cosmetics are provided. 展开更多
关键词 Aloe vera flower chemical composition Biological activity COSMETICS
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Chemical composition and biological activities of Portulaca oleracea
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作者 Haonan Yu Yi’an Shi +3 位作者 Yibo Wang Yunpeng Yang Ying Li Yu Chen 《Asian Journal of Traditional Medicines》 2023年第4期173-202,共30页
Portulaca oleracea(P.oleracea)is a traditional Chinese herbal that has the effects of soothing the liver and clearing collaterals,strengthening the spleen and stomach,moistening the intestines and detoxifying.With the... Portulaca oleracea(P.oleracea)is a traditional Chinese herbal that has the effects of soothing the liver and clearing collaterals,strengthening the spleen and stomach,moistening the intestines and detoxifying.With the development of the pharmaceutical industry,the medicinal value of P.oleracea is becoming increasingly prominent.It is commonly used in clinical practice for clearing heat and detoxifying,inhibiting bacteria,preventing and treating diseases such as hypertension,coronary heart disease,and cerebral infarction,indicating its broad application prospects.This study reviews the chemical components and pharmacological activities of P.oleracea in recent decades. 展开更多
关键词 Portulaca oleracea chemical composition biological activity
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Chemical composition and biological activities of volatile oil isolated from Curcumae rhizoma
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作者 Wenhan Wang Yibo Wang +3 位作者 Yuntian Xing Xinyao Wang Guanyi Zhao Yu Chen 《Asian Journal of Traditional Medicines》 2023年第6期280-288,共9页
Curcumae rhizoma(C.rhizoma),the rhizome of Curcuma Longa L.,Curcuma kwangsiensis L.and Curcuma wenyujin L.in the ginger family,is a treasure in traditional Chinese medicine.It has the effect of promoting qi and breaki... Curcumae rhizoma(C.rhizoma),the rhizome of Curcuma Longa L.,Curcuma kwangsiensis L.and Curcuma wenyujin L.in the ginger family,is a treasure in traditional Chinese medicine.It has the effect of promoting qi and breaking blood,eliminating accumulation and relieving pain.With the development of modern medicine,the active ingredients and therapeutic mechanism of C.rhizoma have been gradually revealed.In this paper,the chemical composition and biological activities of volatile oil isolated from C.rhizoma are reviewed in detail,aiming to provide reference for further utilization of C.rhizoma volatile oil and provide more effective drug options for clinical treatment. 展开更多
关键词 Curcumae rhizoma chemical composition biological activity
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Prediction of Chemical Composition of Ancient Glass Relics before Weathering
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作者 Jiehua Sun Huazhou Chen +3 位作者 Yao Liu Hongquan Lin Huiwen Zheng Yingzhen Qiu 《Open Journal of Applied Sciences》 2023年第9期1565-1580,共16页
Ancient glass relics are easily weathered by the influence of buried environment, and the internal elements exchange with the environmental elements in large quantities, resulting in changes in their composition ratio... Ancient glass relics are easily weathered by the influence of buried environment, and the internal elements exchange with the environmental elements in large quantities, resulting in changes in their composition ratio. Archaeological research can often detect the component content of glass relics after weathering, but it is difficult to obtain the corresponding component content before weathering. It is necessary to predict the chemical composition of glass relics before weathering in order to accurately identify the type of glass relics and repair them. To solve this problem, this paper proposes a distributed matching strategy, and studies the influence of weathering on the composition content of glass through compositional correlation analysis and linear regression statistical methods, so as to build a prediction model of the composition content of glass relics before weathering. The results show that the composition prediction model of glass cultural relics constructed by the distribution matching strategy has a good prediction ability, which is consistent with the change trend of the composition ratio of linear regression analysis. Moreover, the model is simple and easy to operate, which is convenient for popularization and application, and provides theoretical basis and reference value for further research on the composition and accurate classification of glass cultural relics. 展开更多
关键词 Glass Relics WEATHERING chemical composition Correlation Analysis Distribution Matching Model Prediction
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Chemical Compositions of Volatile Oil from Fruiting Body of Armillaria luteo-virens 被引量:30
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作者 周劲松 熊辉岩 +2 位作者 杨春江 焦迎春 盛海彦 《Agricultural Science & Technology》 CAS 2008年第2期90-92,共3页
The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic p... The chemical compositions of volatile oil from fruiting body of Armillaria luteo-virens in Qinghai Province were firstly analyzed with GC-MS and its relevant compositions were detected by calculating chromatographic peak area with normalized method. 21 peaks were separated and 13 compositions were identified which were mainly unsaturated fatty acids, taking 97.1% of the total volatile oil. 展开更多
关键词 Armillaria luteo-rirens Volatile oil chemical compositions GC-MS
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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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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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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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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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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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