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Significant Breakthrough in Industrial Test of the "Methanol to Olefins" Process Developed by Dalian Institute of Chemical Physics,Chinese Academy of Sciences
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《Journal of Natural Gas Chemistry》 CAS CSCD 2006年第4期I0001-I0002,共2页
A process of "Methanol or Dimethylether to Olefins" developed by Dalian Institute of Chemical Physics (DICP), designated as the DMTO process, has attained great success in industrial scaling up testing. DICP, by c... A process of "Methanol or Dimethylether to Olefins" developed by Dalian Institute of Chemical Physics (DICP), designated as the DMTO process, has attained great success in industrial scaling up testing. DICP, by collaborating with the Xinxing Coal Chemical Co., Ltd. of Shaanxi Province and the Luoyang Petrochemical Engineering Co. of the SINOPEC Group, operated successfully a 50t(methanol)/d unit for the conversion of methanol to lower olefins, with a methanol conversion of close to 100%, and a selectivity to lower olefins(ethylene, propylene and butylenes) of higher than 90%. On 23rd August, the industrial test project has passed a state appraisal. The experts of the Appraisal Group, headed by Prof. YUAN Qingtang, academician of Chinese Academy of Engineering, drew the conclusions that the DMTO process, by utilizing a proprietary SAPO-34 catalyst system and a recycling fluidized bed reaction system for the production of lower olefins from methanol, is the first unit in the world having a capacity of producing nearly ten thousand tons lower olefins per year. The technological level of the industrial test is at a leading position internationally. This accomplishment will provide a sound base for the subsequent commercialization of the DMTO process. 展开更多
关键词 Methanol to Olefins Process Developed by Dalian Institute of chemical physics Chinese Academy of Sciences Significant Breakthrough in Industrial Test of the DMTO Test
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Dalian Institute of Chemical Physics/Chinese Academy of Sciences and Elsevier Signed a Publishing Agreement of the Journal of Natural Gas Chemistry
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作者 Editorial Office Journal of Natural Gas Chemistry 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2005年第3期i0001-i0001,共1页
Dalian Institute of Chemical Physics (DICP) /Chinese Academy of Sciences (CAS) and Elsevier have concluded a publishing agreement for the Journa/of Natural Gas Chemistry (JNGC) on June 07, 2005. Beginning from 2... Dalian Institute of Chemical Physics (DICP) /Chinese Academy of Sciences (CAS) and Elsevier have concluded a publishing agreement for the Journa/of Natural Gas Chemistry (JNGC) on June 07, 2005. Beginning from 2006, Elsevier will publish JNGC on ScienceDirect, the online full text and bibliographic information resource, and take care of JNGC's international institutional print subscriptions. JNGC will also be covered in Elsevier's EI Compendex. 展开更多
关键词 Dalian Institute of chemical physics/Chinese Academy of Sciences and Elsevier Signed a Publishing Agreement of the Journal of Natural Gas Chemistry Office
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Dalian Institute of Chemical Physics/Chinese Academy of Sciences and Elsevier Signed a Publishing Agreement of the Journal of Natural Gas Chemistry
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作者 Editorial Office Journal of Natural Gas Chemistry 《Journal of Natural Gas Chemistry》 CAS CSCD 2005年第2期i001-i001,共1页
Dalian Institute of Chemical Physics (DICP) /Chinese Academy of Sciences (CAS) and Elsevier have concluded a publishing agreement for the Journal of Natural Gas Chemistry (JNGC) on June 07, 2005. Beginning from 2006, ... Dalian Institute of Chemical Physics (DICP) /Chinese Academy of Sciences (CAS) and Elsevier have concluded a publishing agreement for the Journal of Natural Gas Chemistry (JNGC) on June 07, 2005. Beginning from 2006, Elsevier will publish JNGC on ScienceDirect, the online full text and bibliographic information resource, and take care of JNGC’s international institutional print subscriptions. JNGC will also be covered in Elsevier’s EI Compendex. 展开更多
关键词 Dalian Institute of chemical physics/Chinese Academy of Sciences and Elsevier Signed a Publishing Agreement of the Journal of Natural Gas Chemistry
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Dalian Institute of Chemical Physics/Chinese Academy of Sciences and Elsevier Signed a Publishing Agreement of the Journal of Natural Gas Chemistry
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作者 Editorial Office Journal of Natural Gas Chemistry 《Journal of Natural Gas Chemistry》 CSCD 2005年第4期I0001-I0001,共1页
Dalian Institute of Chemical Physics (DICP)/Chinese Academy of Sciences (CAS) and Elsevier have concluded a publishing agreement for the Journal of Natural Gas Chemistry (JNGC) on June 07, 2005. Beginning from 2... Dalian Institute of Chemical Physics (DICP)/Chinese Academy of Sciences (CAS) and Elsevier have concluded a publishing agreement for the Journal of Natural Gas Chemistry (JNGC) on June 07, 2005. Beginning from 2006, Elsevier will publish JNGC on ScienceDirect, the online full text and bibliographic information resource, and take care of JNGC's international institutional print subscriptions. JNGC will also be covered in Elsevier's EI Compendex. 展开更多
关键词 Dalian Institute of chemical physics/Chinese Academy of Sciences and Elsevier Signed a Publishing Agreement of the Journal of Natural Gas Chemistry
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Functional Optical Fiber Sensors Detecting Imperceptible Physical/Chemical Changes for Smart Batteries
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作者 Yiding Li Li Wang +3 位作者 Youzhi Song Wenwei Wang Cheng Lin Xiangming He 《Nano-Micro Letters》 SCIE EI CAS CSCD 2024年第8期268-308,共41页
The battery technology progress has been a contradictory process in which performance improvement and hidden risks coexist.Now the battery is still a“black box”,thus requiring a deep understanding of its internal st... The battery technology progress has been a contradictory process in which performance improvement and hidden risks coexist.Now the battery is still a“black box”,thus requiring a deep understanding of its internal state.The battery should“sense its internal physical/chemical conditions”,which puts strict requirements on embedded sensing parts.This paper summarizes the application of advanced optical fiber sensors in lithium-ion batteries and energy storage technologies that may be mass deployed,focuses on the insights of advanced optical fiber sensors into the processes of one-dimensional nano-micro-level battery material structural phase transition,electrolyte degradation,electrode-electrolyte interface dynamics to three-dimensional macro-safety evolution.The paper contributes to understanding how to use optical fiber sensors to achieve“real”and“embedded”monitoring.Through the inherent advantages of the advanced optical fiber sensor,it helps clarify the battery internal state and reaction mechanism,aiding in the establishment of more detailed models.These advancements can promote the development of smart batteries,with significant importance lying in essentially promoting the improvement of system consistency.Furthermore,with the help of smart batteries in the future,the importance of consistency can be weakened or even eliminated.The application of advanced optical fiber sensors helps comprehensively improve the battery quality,reliability,and life. 展开更多
关键词 Smart battery Advanced embedded optical fiber sensor Battery internal physical/chemical state Quality-reliability-life characteristic
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Assessment of the Variations in Soil Physicochemical Parameters of the Natural Forest and Plantations in Orumba North Local Government Area, Anambra State, Nigeria
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作者 Maureen Chinwe Odachi Nwabueze Ikenna Igu Ifeanyi Chris Onwuadiochi 《Journal of Geoscience and Environment Protection》 2024年第10期132-151,共20页
Soil physicochemical parameters are the physical and chemical characteristics of soil such as pH, bulk density, organic carbon, nitrogen content, and nutrient levels at different soil depths. These parameters vary fro... Soil physicochemical parameters are the physical and chemical characteristics of soil such as pH, bulk density, organic carbon, nitrogen content, and nutrient levels at different soil depths. These parameters vary from one vegetation to the other and from one soil to the other. The study assessed the variations in soil physicochemical parameters of the natural forest and plantations in Agu Eke (Eke bush) in Etti village, Nanka and Umunnebo village, Ufuma both located in Orumba North Local Government Area, Anambra State. The experimental research design and stratified random sampling methods were used for the study and a total of 12 soil samples were collected at 30 cm depth from the selected locations of natural forest, cashew and palm plantations. The samples were analyzed using laboratory Varian AA240 Atomic Absorption Spectrophotometer, after which the result was subjected to statistical analysis—Analysis of Variance (ANOVA). The study found that there was no significant difference (variation) between the moisture contents of natural forests and the plantations;that is, the moisture contents were the same. It was also found that there was no significant variation between the bulk densities of the natural forest, oil plantation, and cashew plantation, meaning that the bulk densities were significantly the same. However, there were significant variations in nitrogen, potassium and phosphates, with p-values: sig = .000 < .05, sig = .010 < .05 and sig = .000 < .05, respectively. That is, the nitrogen and phosphate contents of the natural forest significantly vary more than those of the oil palm and cashew plantations, which probably means that by reducing natural forest to plantation, the nitrogen and phosphate contents of the natural forest reduced from what it used to be when the lands were mere forests. This shows that plantations do not have the same function of maintaining or improving soil quality as natural forests. The study recommended adopting a sustainable plantation agricultural system, such as using diverse nutrient sources (manure and compost), in order to maintain the desired soil quality. 展开更多
关键词 ECOSYSTEM Land Use Change Soil Quality Physical and chemical Characteristics
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GIS-Based Assessment of Soil Chemical and Physical Properties as a Basis for Land Reclamation in Toshka Area, Aswan, EGYPT
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作者 Ahmed A. M. Awad Mostafa M. A. Al-Soghir 《Open Journal of Geology》 2023年第7期697-719,共23页
The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the... The accurate assessment of soil properties is a crucial factor for composing and implementing reclamation plans. The main objective of this study was to evaluate soil chemical and physical properties and calculate the chemical and fertility index for assisting land reclamation in Toshka area. The Toshka area is located between latitudes 31°32'N and 31°36'N and longitudes 32°40'E and 32°60'E. GIS was used to select 16 sites. The results revealed the soil has undesirable characteristics. The soil pH ranged from slightly alkaline to moderately alkaline. Furthermore, it was characterized as saline (with a ECe of 4.65 - 11.45 dS⋅m<sup>−1</sup>) and moderately calcareous soil (with CaCO<sub>3</sub> at 11.85% - 17.20%). The soil had a low soil organic matter content which did not exceed 0.18%. The soil was dominated by a sandy loam texture (62.50%) followed by a sandy clay loam texture (18.75%). The bulk density, total soil porosity and saturated hydraulic conductivity values varied with 1.38 - 1.55 Mg⋅cm<sup>−3</sup>, 41.85% - 48.45% and 1.20 - 3.34 cm⋅h<sup>−1</sup>, respectively. The chemical index ranged from low to moderate quality. The correlations between the parameters osculated between negative and positive. Therefore, the soil may be reclaimed if the soil properties are improved and crop selection is optimized for this soil. 展开更多
关键词 Land Reclamation Soil chemical and Physical Properties chemical Quality Index Fertility Quality Index
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Extended wet sieving method for determination of complete particle size distribution of general soils 被引量:1
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作者 Shengnan Ma Yi Song +2 位作者 Jiawei Liu Xingyu Kang Zhongqi Quentin Yue 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第1期242-257,共16页
The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional meth... The traditional standard wet sieving method uses steel sieves with aperture?0.063 mm and can only determine the particle size distribution(PSD)of gravel and sand in general soil.This paper extends the traditional method and presents an extended wet sieving method.The extended method uses both the steel sieves and the nylon filter cloth sieves.The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm,0.038 mm,0.014 mm,0.012 mm,0.0063 mm,0.004 mm,0.003 mm,0.002 mm,and 0.001 mm,respectively.The extended method uses five steps to separate the general soil into many material sub-groups of gravel,sand,silt and clay with known particle size ranges.The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups.The extended method is demonstrated with a general soil of completely decomposed granite(CDG)in Hong Kong,China.The silt and clay materials with different particle size ranges are further examined,checked and verified using stereomicroscopic observation,physical and chemical property tests.The results further confirm the correctness of the extended wet sieving method. 展开更多
关键词 Particle size distribution(PSD) General soil SILT CLAY Wet sieving Physical and chemical properties
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Changing Rules of Physical and Chemical Properties of Eucalyptus uraphylla spp. Forest at Different Ages in Southwest Yunnan Province 被引量:5
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作者 赵筱青 丁宁 闫平 《Agricultural Science & Technology》 CAS 2012年第6期1298-1302,共5页
[Objective] The aim was to study on changing rules of physical and chemical properties of Eucalyptus uraphylla spp. forest at different ages in Southwest of Yunnan Province. [Method] In the research, field survey and ... [Objective] The aim was to study on changing rules of physical and chemical properties of Eucalyptus uraphylla spp. forest at different ages in Southwest of Yunnan Province. [Method] In the research, field survey and laboratory analysis were adopted to study on physical and chemical properties of soils for the Eucalyptus uraphylla spp. at the first cutting ages in Lancang County. [Result] With the increasing of forest ages, for physical properties of soils, soil bulk density was increasing, and soil structure became poor; water contents in soils and capillary porosity were improving, but total soil porosity and non-capillary porosity were decreasing. For chemical properties, pH of soil dropped, but soil acidity improved; organic matter, total N, hydrolysable nitrogen, available phosphorus, and available potassium all declined; exchangeable Ca and Mg were improving due to fertilization and Ca and Mg lower consumption. The results showed that plays important roles in water absorption of soils and vegetation growth were improved with age increase by Eucalyptus uraphylla spp. forest, but ventilation and fertility declined accordingly. [Conclusion] The research indicated that dry branches and fallen leaves should be preserved and nutrient cycling should be protected during introduction and management of Eucalyptus uraphylla spp. to guarantee the nutrients in dry branches and leaves are back to soils, providing theoretical references for management of forest plantation and environment protection. 展开更多
关键词 Eucalyptus uraphylla spp. Physical and chemical properties Soil fertility Lancang County
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Optimization and Characterization of Combined Degumming Process of Typha angustata L. Stem Fibers
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作者 Sana Rezig Foued Khoffi +2 位作者 Mounir Jaouadi Asma Eloudiani Slah Msahli 《Journal of Renewable Materials》 EI CAS 2024年第6期1071-1086,共16页
Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers.Researchers over the years have explored many plant fibers using different extraction processes to... Plant derived natural fibers have been widely investigated as alternatives to synthetic fibers in reinforcing polymers.Researchers over the years have explored many plant fibers using different extraction processes to study their physical,chemical,and mechanical properties.In this context,the present study relates to the extraction,characterization,and optimization of Typha angustata L.stem fibers.For this purpose,desirability functions and response surface methodology were applied to simultaneously optimize the diameter(D),linear density(LD);yield(Y),lignin fraction(L),and tenacity(T)of Typha stem fibers.Typha stems have been subjected to both alkali(NaOH)and enzymatic(pectinex ultra-SPL)treatments.Three levels of process variables including enzyme concentration(10,15,and 20 ml/L)and treatment duration(10,15,and 20 days)were used to design the experiments according to the factorial design.Experimental results were examined by analysis of variance and fitted to second order polynomial model using multiple regression analysis.The Derringer’s desirability function released that the values of process variables generating optimized diameter,linear density,yield,lignin ratio and tenacity are 20 ml/L and 20 days for concentration of pectinex ultra-SPL enzyme and treatment duration,respectively.Confirmation was performed and high degree of correlation was found between the experimental and statistical values.Moreover,the morphological structure has been investigated by the scanning electron microscope,showing a crenelated structure of ultimate fiber bundles of cellulose composing the Typha fiber.Compared to Typha stem non-treated fibers(TSNTF),Typha stem combined treated fibers(TSCTF),brings to improve mechanical properties.This change in mechanical properties is affected by modifying the fiber structure showing alpha cellulose of(66.86%)and lignin ratio of(10.83%)with a crystallinity index of(58.47%). 展开更多
关键词 Typha angustata L.stems fibers combined treatment optimization process desirability function chemical and physical properties morphological structure
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Changing Rule of Physical and Chemical Indicators of Sediment in Tilapia Aquaculture Ponds
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作者 裘丽萍 李志波 +4 位作者 宋超 张聪 郑尧 孙博 陈家长 《Agricultural Science & Technology》 CAS 2016年第3期690-693,699,共5页
To provide basic information for studying balancing mechanism of nutrition environment in aquaculture ponds, sediment samples were collected periodically during the breeding process of tilapia in ponds. Then various t... To provide basic information for studying balancing mechanism of nutrition environment in aquaculture ponds, sediment samples were collected periodically during the breeding process of tilapia in ponds. Then various types of nutrient content of the samples were detected and the changing rule was summarized. The results showed that dry weight of the sediment and content of TP, TN and TOC generally presented a trend of first increasing and then decreasing. The main production period of each nutrient was from July to September and the production percentage was close to 80% of the total production. The content of NH4^+-N increased gradually and reached a peak in early August, then maintained at the peak level. NO2^--N content of the sediment in each pond was basically the same in the earlier aquaculture stage and decreased in middle stage with a big difference, then rose again in the later stage. 展开更多
关键词 TILAPIA SEDIMENT Physical and chemical indicators Changing rule
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Ecological effect of the plantation of Sabina vulgaris in the Mu Us Sandy Land,China
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作者 NAN Weige DONG Zhibao +2 位作者 ZHOU Zhengchao LI Qiang CHEN Guoxiang 《Journal of Arid Land》 SCIE CSCD 2024年第1期14-28,共15页
Vegetation restoration through artificial plantation is an effective method to combat desertification,especially in arid and semi-arid areas.This study aimed to explore the ecological effect of the plantation of Sabin... Vegetation restoration through artificial plantation is an effective method to combat desertification,especially in arid and semi-arid areas.This study aimed to explore the ecological effect of the plantation of Sabina vulgaris on soil physical and chemical properties on the southeastern fringe of the Mu Us Sandy Land,China.We collected soil samples from five depth layers(0-20,20-40,40-60,60-80,and 80-100 cm)in the S.vulgaris plantation plots across four plantation ages(4,7,10,and 16 years)in November 2019,and assessed soil physical(soil bulk density,soil porosity,and soil particle size)and chemical(soil organic carbon(SOC),total nitrogen(TN),available nitrogen(AN),available phosphorus(AP),available potassium(AK),cation-exchange capacity(CEC),salinity,p H,and C/N ratio)properties.The results indicated that the soil predominantly consisted of sand particles(94.27%-99.67%),with the remainder being silt and clay.As plantation age increased,silt and very fine sand contents progressively rose.After 16 years of planting,there was a marked reduction in the mean soil particle size.The initial soil fertility was low and declined from 4 to 10 years of planting before witnessing an improvement.Significant positive correlations were observed for the clay,silt,and very fine sand(mean diameter of 0.000-0.100 mm)with SOC,AK,and p H.In contrast,fine sand and medium sand(mean diameter of 0.100-0.500 mm)showed significant negative correlations with these indicators.Our findings ascertain that the plantation of S.vulgaris requires 10 years to effectively act as a windbreak and contribute to sand fixation,and needs 16 years to improve soil physical and chemical properties.Importantly,these improvements were found to be highly beneficial for vegetation restoration in arid and semi-arid areas.This research can offer valuable insights for the protection and restoration of the vegetation ecosystem in the sandy lands in China. 展开更多
关键词 Sabina vulgaris plantation age soil physical and chemical properties soil particle size soil fertility vegetation restoration Mu Us Sandy Land
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Soil Physical and Chemical Properties of Five Subtropical Forests in Lingao of Hainan
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作者 薛杨 宿少锋 +1 位作者 王小燕 林之盼 《Agricultural Science & Technology》 CAS 2017年第8期1459-1464,共6页
With 5 types of typical forests as research object, the physical and chemical properties of different types of forests were analyzed by sample plot investigation method. The results showed that: the soil total porosi... With 5 types of typical forests as research object, the physical and chemical properties of different types of forests were analyzed by sample plot investigation method. The results showed that: the soil total porosity was the highest in the Casuarina equisetifolia forest (46.168%), but the lowest in the Encalyptus robusta forest (39.46%). The soil capillary porosity was the highest in the Acacia mangium forest (22.57%), but the lowest in the secondary forest (18.95%). The soil water content was the highest in the C. equisetifolia forest, with a mean value of 27.85%, but the lowest in the secondary forest, with a mean value of 4.34%. The soil pH values were in the range of 4.81-6.59, the soils in the A. mangium forest, C. equisetifolia forest and E. robusta forest were strongly acidic (pH 4.5-5.5), and the soils in the secondary forest and C. nucifera forest were weakly acidic. The soils had organic matter contents in the range of 0.34-28.68 g/kg, and showed an order of A. mangium forest〉C. equisetifolia forest〉E. robusta forest〉secondary forest〉C. nucifera forest, with a decreasing trend with the soil depth increasing. The soil total N contents were in the range of 0.10-1.63 g/kg, the A. mangium forest showed the highest soil total N contents, while the C. nucifera forest exhibited the lowest soil total N contents; the soil total P contents were in the range of 0.21-1.74 g/kg, and the E. robusta forest had the highest soil total P contents; and the soil total K contents were in the range of 0.16-2.15 g/kg, and the A. mangium forest exhibited the highest soil total K contents. The soil available P contents were in the range of 0.98-132.46 mg/kg; and the secondary forests had the highest soil available P contents; and the soil rapidly available K contents were in the range of 3.03-27.35 mg/kg, and the C. nucifera forest exhibited the highest soil rapidly available K contents. The soil ammonium N contents were in the range of 1.38-5.15 mg/kg, and the nitrate N contents were in the range were in the range of 0.56 -3.51 mg/kg. The A. mangium forest showed the highest soil nitrate N contents (with a mean value of 2.29 mg/kg) and ammonium N contents (with a mean value of 3.93 mg/kg). For the same forest type, with the increase of soil depth, the nitrate nitrogen and ammonium nitrogen content also showed a decreasing trend. 展开更多
关键词 Lingao County Coastal platform Different forest types Soil physical and chemical properties COMPARISON
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Research on Physical and Chemical Properties of Corynebacterium glutamicum in Fermentation Process of the Glucose of Wheat Starch
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作者 黄继红 周靖波 欧歌 《Agricultural Science & Technology》 CAS 2013年第3期516-519,共4页
[Objective] This study aimed to investigate the physical and chemical char- acteristic of Corynebacterium glutamicum in fermentation process of the glucose of wheat starch. [Method] The purity of glutamic acid in ferm... [Objective] This study aimed to investigate the physical and chemical char- acteristic of Corynebacterium glutamicum in fermentation process of the glucose of wheat starch. [Method] The purity of glutamic acid in fermentation period, optical density and cell viability of bacteria were detected as indicators for regression com- parison and analysis. [Result] The relative error d=-3.316 6% within the experimental range of Warburg trace breathing apparatus and double function analyzer. The linear relationship was s1=(1-d)s2. During the fermentation process of the glucose of wheat starch, the average cell activity was 6.24 μA and the maximum cell activity was 6.61 μA. [Conclusion] Compared with optical density, cell viability can more accurate- ly reflect the physical and chemical properties of Corynebacterium glutamicum in fermentation process of the glucose of wheat starch. There was certain correlation between cell membrane phospholipids and cell viability. 展开更多
关键词 Glucose of wheat starch Glutamic acid Cell viability Physical and chemical characteristic
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Recent advances on application of polysaccharides in cosmetics
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作者 Qingyuan Wu Na Cheng +4 位作者 Danjiao Fang Hao Wang Faiz-Ur Rahman Huifang Hao Yongmin Zhang 《Journal of Dermatologic Science and Cosmetic Technology》 2024年第1期21-36,共16页
Natural products have attracted wide attention in the cosmetics market due to their safety and high efficiency.As a highly active substance in nature,natural polysaccharides have been reported in recent years to have ... Natural products have attracted wide attention in the cosmetics market due to their safety and high efficiency.As a highly active substance in nature,natural polysaccharides have been reported in recent years to have various cosmetic activities such as moisturizing,whitening,anti-aging and repairing skin,and are becoming a hot research topic in the cosmetics industry.At present,the mechanism of polysaccharide exerting cosmetic activity has been widely studied,but the relationship between polysaccharide’s chemical structure and cosmetic activity has not been effectively analyzed,which leads to the limitation of polysaccharide development.In this review,the mechanism of polysaccharides exerting cosmetic activities such as moisturizing,whitening,anti-aging and skin repair was introduced.The potential relationship between the structure and activity of polysaccharides was summarized by analyzing the influence of physical and chemical properties of polysaccharides,such as extraction method,molecular weight,monosaccharide composition,functional group and structural modification,etc.,which laid a foundation for the analysis of the structure-activity relationship of polysaccharides and improved its cosmetic value. 展开更多
关键词 POLYSACCHARIDE COSMETICS Physical and chemical properties Structure-activity relationship Biological activity
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Progress on the melanoidins produced by the Maillard reaction of fermented food and traditional Chinese medicine
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作者 Guang-Zhen Cao Si-Yi Zhang +4 位作者 Yao-Song Yang Qing He Xin-Xian Song Fei Long Teng Peng 《Food and Health》 2024年第4期10-18,共9页
FMs(Food-borne melanoidins)are brown high molecular weight polymers formed by the Mailiard reaction between carbohydrates and nitrogen-containing compounds during the processing of food or Traditional Chinese Medicine... FMs(Food-borne melanoidins)are brown high molecular weight polymers formed by the Mailiard reaction between carbohydrates and nitrogen-containing compounds during the processing of food or Traditional Chinese Medicine(TCM),and are widely found in food-borne products such as TCM concoctions,bakery,brewing,soy sauce,ferment and other food-borne products.FMs not only have a variety of biological activities,such as antioxidant,antibacterial,immunomodulation,regulation of intestinal flora,etc.,and can change the color,aroma and taste of food.The diversity of its components has become a research hotspot at home and abroad in recent years,with a wide range of application prospects.Therefore,this paper summarizes the existing information on FMs at home and abroad,mainly describes their preparation process,physicochemical properties,structural characteristics and functional activity research progress.Typical FMs,such as coffee,biscuits,wine and soy sauce in daily food,and Polygonatum,Perilla oil,Black ginseng,and Red jujube in T,were highlighted.Summarising the current status of research between the chemistry and pharmacodynamics of relevant FMs and presenting challenges and future recommendations for melanoidin research.In future research on FMs,one should pay more attention to basic research,especially isolation and purification and generation mechanisms,to further demonstrate the biological activity of FMs in vivo and in clinical trials.Thus,the potential value of its existence is deeply exploited to meet the needs of technology,production and health. 展开更多
关键词 Food-borne melanoidins Physical and chemical properties Structure Functional activities Application prospects
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Classification and Distribution of Common Aroma Components in Tobacco Leaf Based on Their Physical and Chemical Properties 被引量:4
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作者 詹军 周芳芳 +6 位作者 朱海滨 高侠飞 毛春堂 王柱石 严君 陈少鹏 张晓龙 《Agricultural Science & Technology》 CAS 2013年第9期1358-1364,共7页
[Objective] This study was aimed to find a new method for the classification of common aroma components in tobacco leaves. [Method] Sixty-four common aroma components in tobacco leaves were classified by cluster analy... [Objective] This study was aimed to find a new method for the classification of common aroma components in tobacco leaves. [Method] Sixty-four common aroma components in tobacco leaves were classified by cluster analysis based on their relative molecular weight. The contents and distribution of aroma components in another 71 C3F and 64 B2F tobacco leaf samples were analyzed by using the new method. [Result] The 64 common aroma components were divided into three categories trough the cluster analysis based on their molecular weight. CategoryⅠ consisted of 12 aroma components which had high molecular weight(281.308±21.536on average) and high boiling point(371.311±29.904 ℃ on average). Category Ⅱ included 27 components which had low molecular weight(103.722 ± 13.115 on average) and low boiling point(176.132±42.342 ℃ on average). Category Ⅲ included 25components which had middle molecular weight(175.393 ± 24.906 on average) and middle boiling point(250.562±45.431 ℃ on average). The content of high-molecularweight aroma components in middle leaves(547.344±224.391 μg/g) was much higher than that in upper leaves(477.549±182.066 μg/g). The content of low-molecularweight aroma component in middle leaves(17.468±3.459 μg/g) was also significantly higher than that in upper leaves(15.936±3.456 μg/g). The content of middle-molecular-weight aroma component in middle leaves(44.931 ±8.953 μg/g) was extremely significantly higher than that in upper leaves(37.997±6.042 μg/g). [Conclusion] This study proposed a new way to classify the aroma components in flue-cured tobacco leaves using the relative molecular weight as the index, which will provide theoretical reference for developing special tobacco leaves. 展开更多
关键词 Physical and chemical properties Flue-cured tobacco Aroma components Molecular weight Boiling point DENSITY CLASSIFICATION
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Effects of Green Manure Mixed Cropping Patterns on Physical and Chemical Properties of Soil and Economic Characters of Flue-cured Tobacco 被引量:4
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作者 陈治锋 邓小华 +2 位作者 周米良 田峰 张明发 《Agricultural Science & Technology》 CAS 2015年第8期1723-1727,共5页
[Objective] The aim was to clear the suitable green manure cropping pat- terns in Xiangxi tobacco-planting areas. [Method] 8 treatments were set to study the effects of the monoculture and mixed cropping of common vet... [Objective] The aim was to clear the suitable green manure cropping pat- terns in Xiangxi tobacco-planting areas. [Method] 8 treatments were set to study the effects of the monoculture and mixed cropping of common vetch (Vicia gigantea Bge.), perennial ryegrass (Lofium) and rapeseed (Brassica campestris L.) on physi- cal and chemical properties of soil and economic characters of flue-cured tobacco. [Result] (1) Green manure turnover can reduce soil bulk density by 1.08%-8.62%, and the effect of green manure mixed cropping pattern was the best. (2) Green manure turnover also can increase the soil nutrient, soil organic matter, total nitro- gen (N), total phosphorus (P), total potassium (K), alkali-hydrolyzale N, rapidly available P and rapidly available K by 1.44%-6.10%, 0.01-0.12 g/kg, 1.89%- 11.32%, 0.12%-3.56%, 1.06%-11.76%, 0.04%-18.93% and 0.98%-23.12%, respec- tively, and the effect of the monoculture of common vetch was the best.(3) The overall change of soil pH was not obvious.(4)Green manure turnover can increase the yield and output of flue-cured tobacco, and the effect of the monoculture of common vetch was the best. [Conclusion] The monoculture of common vetch can be generalized in the dry land of Xiangxi tobacco-planting areas. 展开更多
关键词 Green manure Mixed cropping Soil physical and chemical properties Economic characters of flue-cured tobacco
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Effect of fire severity on physical and biochemical soil properties in Zagros oak(Quercus brantii Lindl.)forests in Iran 被引量:16
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作者 M.Heydari A.Rostamy +1 位作者 F.Najafi D.C.Dey 《Journal of Forestry Research》 SCIE CAS CSCD 2017年第1期95-104,共10页
Fire affects the physical and chemical properties and soil biological activity of natural ecosystems. This study was conducted in the Miyan Tang region, Ilam Province in western Iran. The study site was 110 hectares, ... Fire affects the physical and chemical properties and soil biological activity of natural ecosystems. This study was conducted in the Miyan Tang region, Ilam Province in western Iran. The study site was 110 hectares, where we sampled soils in areas that were classified by fire severity: low (LS), high (HS) and medium severity (MS), and unburned (UB), which served as the control. In each severity class, 25 transect points were randomly selected for measurement. Around each transect plot center, 3 soil samples were selected randomly and soils collected from the 0 to 20 cm depth were combined into a composite sample that was used in laboratory analysis to represent conditions at that point. Plots in the UB and LS fire classes had similar soil conditions and had higher values of factors such as saturated moisture, organic carbon, carbon dioxide, and silt and clay content. In contrast, plots in the HS and MS fire severity classes were clustered in the positive direction along the first axis that represented gradients in soil acidity, electrical conductivity, cation exchange capacity, accessible phosphorus, accessible potassium, bulk density, and sand. Soil attributes were similar in areas of HS and MS fire severity classes, whereas soil conditions in the LS class and UB controls were most similar. Fire in the LS areas either did not significantly alter the physicalchemical soil properties and microbial basal respiration, or soils were able to recover quickly after being burned. 展开更多
关键词 Fire severity OAK Soil respiration Physical and chemical soil properties
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Effects of Crude Oil Contamination on Soil Physical and Chemical Properties in Momoge Wetland of China 被引量:12
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作者 WANG Ying FENG Jiang +3 位作者 LIN Qianxin LYU Xianguo WANG Xiaoyu WANG Guoping 《Chinese Geographical Science》 SCIE CSCD 2013年第6期708-715,共8页
Large oilfields are often coincidentally located in major river deltas and wetlands,and potentially damage the structure,function and ecosystem service values of wetlands during oil exploration.In the present study,th... Large oilfields are often coincidentally located in major river deltas and wetlands,and potentially damage the structure,function and ecosystem service values of wetlands during oil exploration.In the present study,the effects of crude oil contamination during oil exploration on soil physical and chemical properties were investigated in marshes of the Momoge National Nature Reserve in Jilin Province,China.The concentrations of total petroleum hydrocarbons in the marsh soil near the oil wells are significantly higher than those in the adjacent control marsh.Soil water contents in oil-contaminated marshes are negatively correlated with soil temperature and are significantly lower than those in the control area,especially in fall.Crude oil contamination significantly increases the soil pH up to8.0,and reduces available phosphorus concentrations in the soil.The concentrations of total organic carbon are significantly different among sampling sites.Therefore,crude oil contamination could potentially alkalinize marsh soils,adversely affect soil fertility and physical properties,and cause deterioration of the marshes in the Momoge National Nature Reserve.Phyto-remediation by planting Calamagrostis angustifolia has the potential to simultaneously restore and remediate the petroleum hydrocarbon-contaminated wetlands.Crude oil contamination affects the soil physical and chemical properties,so developing an effective restoration program in the Momoge wetland is neccesary. 展开更多
关键词 crude oil contamination marsh soil oilfield in marshes soil physical and chemical properties WETLAND Momoge National Nature Reserve
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