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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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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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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 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 compositions and pharmacological activities ofXanthium strumarium
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作者 Ruoming Li Yunpeng Yan +4 位作者 Xiaomeng Zhangc Yibo Wang Wenhan Wang Yao Zhao Yu Chena 《Asian Journal of Traditional Medicines》 2024年第6期342-352,共11页
Xanthium strumarium(X.strumarium)is a traditional Chinese medicine with a long history.In recent years,with the development of modern pharmacology and chemical analysis technology,research on X.strumarium has been dee... Xanthium strumarium(X.strumarium)is a traditional Chinese medicine with a long history.In recent years,with the development of modern pharmacology and chemical analysis technology,research on X.strumarium has been deepend.This paper aims to systematically summarize the chemical compositions and pharmacological effects of X.strumarium,in order to provide theoretical basis and reference for further exploration in its clinical application and drug development. 展开更多
关键词 Xanthium strumarium chemical composition pharmacological activities
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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 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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Study of the Chemical and Mineralogical Composition of Kindia Bauxite in the Republic of Guinea: The Case of the Saföfö Site
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作者 Mouctar Camara Mamadouba Aboubacar Fofana +4 位作者 Mohamed Dubréka Sylla Alpha Madiou Diallo Aboubacar Diallo Aly Hawa Camara Sékou Traore 《Journal of Materials Science and Chemical Engineering》 2024年第10期62-71,共10页
The chemical and mineralogical composition of bauxite deposits is a key factor in the profitability of refining processes. The study of bauxites from the Saföfö site has assessed variations in chemical and m... The chemical and mineralogical composition of bauxite deposits is a key factor in the profitability of refining processes. The study of bauxites from the Saföfö site has assessed variations in chemical and mineralogical composition under various conditions, as well as the optimum conditions for their exploitation. The methodologies used in this study include experimental methods for determining moisture content, chemical composition, mineralogical composition, and specific density of bauxite. The results show significant variation in moisture content among the bauxite samples, with values ranging from 2.90% to 17.80%. The silica percentages in the samples range from 1.69% to 8.14%, while alumina percentages vary from 36.81% to 54.03%. After calcination, alumina oxide percentages range from 40% to 75%. After chemical activation, alumina oxides Al2O3 range from 40% to over 50%. Gibbsite is the most abundant mineral, accounting for about 60% - 70% of the total composition of the bauxite samples. Samples A to F have bulk densities varying between approximately 3.6 and 3.9. Sample B has the highest density, around 3.9, while sample C has the lowest, at around 3.5. Bauxite mining at the Saföfö site offers significant potential for the alumina industry, provided appropriate processing methods are selected to maximize quality and profitability while minimizing environmental impact. 展开更多
关键词 BAUXITE chemical composition GUINEA Mineralogy and Saföfö
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Characterization of chemical composition of high viscosity heavy oils:Macroscopic properties, and semi-quantitative analysis of molecular composition using high-resolution mass spectrometry
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作者 Jian-Xun Wu Shuo-Fan Li +6 位作者 Qi-Fu Li Feng Yan Qi-Lin Zhou Shuai Ma Ya-He Zhang Suo-Qi Zhao Quan Shi 《Petroleum Science》 SCIE EI CAS CSCD 2024年第5期3612-3620,共9页
Heavy oil is an important resource in current petroleum exploitation, and the chemical composition information of heavy oil is crucial for revealing its viscosity-inducing mechanism and solving practical exploitation ... Heavy oil is an important resource in current petroleum exploitation, and the chemical composition information of heavy oil is crucial for revealing its viscosity-inducing mechanism and solving practical exploitation issues. In this study, the techniques of high-temperature gas chromatography and high-resolution mass spectrometry equipped with an electrospray ionization source were applied to reveal the chemical composition of typical heavy oils from western, central, and eastern China. The results indicate that these heavy oils display significant variations in their bulk properties, with initial boiling points all above 200℃. Utilizing pre-treatment and ESI high-resolution mass spectrometry, an analysis of the molecular composition of saturated hydrocarbons, aromatic hydrocarbons, acidic oxygen compounds, sulfur compounds, basic nitrogen compounds, and neutral nitrogen compounds within the heavy oil was conducted. Ultimately, a semi-quantitative analysis of the molecular composition of the heavy oil was achieved by integrating the elemental content. The semi-quantitative analysis results of Shengli-J8 heavy oil and a conventional Shengli crude oil show that Shengli-J8 heavy oil lacks alkanes and low molecular weight aromatic hydrocarbons, which contributes to its high viscosity. Additionally,characteristic molecular sets for different heavy oils were identified based on the semi-quantitative analysis of molecular composition. The semi-quantitative analysis of molecular composition in heavy oils may provide valuable reference data for establishing theoretical models on the viscosity-inducing mechanism in heavy oils and designing viscosity-reducing agents for heavy oil exploitation. 展开更多
关键词 Heavy oil HRMS Molecular composition Semi-quantitative analysis VISCOSITY
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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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The Ratio of Flesh to Body and Analysis on Biochemical Composition of Muscle in Pachyhynobius Shangchengensis 被引量:2
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作者 彭仁海 张丽霞 《Agricultural Science & Technology》 CAS 2008年第1期111-116,142,共7页
[Objective] The ratio of flesh content and biochemical compositions in muscles of Pachyhynobius shangchengensis were researched in this experiment to provide basic referrences for studying nutritive physiological ecol... [Objective] The ratio of flesh content and biochemical compositions in muscles of Pachyhynobius shangchengensis were researched in this experiment to provide basic referrences for studying nutritive physiological ecology of Pachyhynobius shangchengensis. [Method] The biochemical analytic method was used to detect the ratio of flesh content and biochemical compositions in muscle of Pachyhynobius shangchengensis. [Result] The ratio of flesh contents of female and male Pachyhynobius shangchengensis were 54.93% and 55.84% respectively. The contents of protein, total saccharides and fatty acid of female Pachyhynobius shangchengensis were 15.44% ,1.70% and 0.68% respectively,while the same contents of male Pachyhynobius shangchengensis were 15.67%, 1.89% and 0.53% respectively. The total content of 18 kinds of amino acids was 12.72% (the proportion in fresh weight), among which the content of 8 kinds of essential amino acids was 4.68%. The essential amino acids index(EAAI) was 72.68 and limiting amino acids was valine. There were 11 kinds of fatty acids in muscles of Pachyhynobius shangchengensis, among which the content of unsaturated fatty acids (80.02%) was higher than that of saturated fatty acids( 19.98% ). [ Conclusion] Pachyhynobius shangchengensis was a kind of valuable natural resource belonging to the nutritious type of low fat content and high protein content. 展开更多
关键词 Pachyhynobius shangchengensis Ratio of flesh content Biochemical compositions in muscle
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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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The autophagy-lysosome pathway:a potential target in the chemical and gene therapeutic strategies for Parkinson’s disease
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作者 Fengjuan Jiao Lingyan Meng +1 位作者 Kang Du Xuezhi Li 《Neural Regeneration Research》 SCIE CAS 2025年第1期139-158,共20页
Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular... Parkinson’s disease is a common neurodegenerative disease with movement disorders associated with the intracytoplasmic deposition of aggregate proteins such asα-synuclein in neurons.As one of the major intracellular degradation pathways,the autophagy-lysosome pathway plays an important role in eliminating these proteins.Accumulating evidence has shown that upregulation of the autophagy-lysosome pathway may contribute to the clearance ofα-synuclein aggregates and protect against degeneration of dopaminergic neurons in Parkinson’s disease.Moreover,multiple genes associated with the pathogenesis of Parkinson’s disease are intimately linked to alterations in the autophagy-lysosome pathway.Thus,this pathway appears to be a promising therapeutic target for treatment of Parkinson’s disease.In this review,we briefly introduce the machinery of autophagy.Then,we provide a description of the effects of Parkinson’s disease–related genes on the autophagy-lysosome pathway.Finally,we highlight the potential chemical and genetic therapeutic strategies targeting the autophagy–lysosome pathway and their applications in Parkinson’s disease. 展开更多
关键词 AUTOPHAGY chemical therapy gene therapy Parkinson’s disease Α-SYNUCLEIN
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A Comparative Study on Chemical Composition of Supercritical CO_2 Extraction Products in Peels of Trichosanthes kirilowii Maxim. from Changqing District
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作者 于京平 李佳 +1 位作者 张永清 范英才 《Agricultural Science & Technology》 CAS 2013年第2期257-261,共5页
[Objective] This study aimed to investigate the differences in chemical composition of supercritical CO2 extraction products in peels of Trichosanthes kirilowii Maxim. from Changqing district. [Method] Supercritical f... [Objective] This study aimed to investigate the differences in chemical composition of supercritical CO2 extraction products in peels of Trichosanthes kirilowii Maxim. from Changqing district. [Method] Supercritical fluidextraction (SFE) and GCMS method were applied to determine and analyze the chemical components of the extracts in peels of three strains of Trichosanthes kirilowii Maxim. [Result] The chemical components of supercritical CO2 extraction products in peels of three strains of Trichosanthes kirilowii Maxim. varied., and the number of chemical components with normalized percentage content higher than 1% was 5, 7 and 8, respectively. There are 14 kinds of common components, and the relative content of hexadecanoic acid was the highest. [Conclusion] Supercritical CO2 extracts in peels of different strains of Trichosanthes kirilowii Maxim. contain different chemical components, providing scientific basis for breeding excellent varieties and the development and utilization of Trichosanthes kirilowii Maxim. 展开更多
关键词 Trichosanthes kirilowii Maxim. PEEL Supercritical CO2 extraction products chemical components COMPARISON
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Physical and Chemical Properties of Horns Sheaths Particles for the Manufacture of Composite Materials
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作者 Tawe Laynde Zakari Yaou +2 位作者 Karga Tapsia Lionel Konai Noel Danwe Raidandi 《Journal of Materials Science and Chemical Engineering》 2024年第5期1-9,共9页
Salvaged cow horns from slaughterhouses have been transformed into fine particles for a physical characterization that has led us to determine the humidity rate (2.34% ± 0.054%), the actual density situated betwe... Salvaged cow horns from slaughterhouses have been transformed into fine particles for a physical characterization that has led us to determine the humidity rate (2.34% ± 0.054%), the actual density situated between 0.586 g/cm<sup>3</sup> and 0.732 g/cm<sup>3</sup>, the swelling rate (12%), and one chemical characterization that permitted us to determine the rate of dry matters (97.05%), of mineral matters (2.5%), of protein matters (94.52%). From these weak values, it can easily be seen that cow horn case doesn’t absorb much water and improve the mechanical characteristics of the composite;the high rate of protein shows that keratin which is the structural molecule favors its gripping as reinforcing element in the manufacturing of composite materials. 展开更多
关键词 HORNS Fibers Polymer Loads Physical Properties chemical composition
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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
20
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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