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Effects of Plastic Film Mulching on Physical Characters of Soil and Yield and Yield Components of Sweet Potato 被引量:5
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作者 张超凡 黄艳岚 +2 位作者 周虹 张亚 张道微 《Agricultural Science & Technology》 CAS 2015年第11期2379-2385,2393,共8页
Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of ... Field experiments were carried out to study the effects of plastic film mulching on soil physical characters, including soil temperature, soil moisture content and soil bulk density, and yield and yield components of sweet potato. The results showed that plastic filming mulching increased soil temperature. Considering the soil temperature-increasing effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. However, with the deepening of soil layer, the warming effect of plastic film mulching was weakened. Black or white plastic film mulching was conducive to low T/R value, especially in the early growth stage of sweet potato. Plastic film mulching significantly improved the storage root yield of sweet potato. In terms of yield-improving effect, the treatments ranked as black plastic film treatment 〉 white plastic film treatment 〉 control. The storage root num- ber per plant showed a downward trend, but the weight of single storage root was increased. 展开更多
关键词 Plastic film mulching Sweet potato Soil physical characters YIELD Growth and development
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A new interpolation method based on satellite physical character in using IGS precise ephemeris 被引量:4
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作者 Liu Weiping Hao Jinming 《Geodesy and Geodynamics》 2014年第3期29-33,共5页
Due to the deficiency of sliding Lagrange polynomial interpolation, the author proposes a new interpolation method, which considers the physical character of satellite movement in coordinate transformation and reasona... Due to the deficiency of sliding Lagrange polynomial interpolation, the author proposes a new interpolation method, which considers the physical character of satellite movement in coordinate transformation and reasonable selection of interpolation function. Precision of the two methods is compared by a numerical example. The result shows that the new method is superior to the sliding Lagrange polynomial interpolation in interpolation and extrapolation, especially in extrapolation that is over short time spans. 展开更多
关键词 precise ephemeris INTERPOLATION trigonometric interpolation coordinate transformation physical character
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Recent developments in the physical structure of solid formulations:a comprehensive review
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作者 Zhe Li Xiaosui Luo +8 位作者 Abid Naeem Qiong Li Yao Zhang Yongmei Guan Lihua Chen Weifeng Zhu Zhengji Jin Yi Feng Liangshan Ming 《Journal of Chinese Pharmaceutical Sciences》 CAS CSCD 2024年第10期877-905,共29页
Solid formulations represent the most widely used dosage forms,and their structural attributes significantly impact the efficacy of drugs.Consequently,delving into the study of solid formulation structures is of param... Solid formulations represent the most widely used dosage forms,and their structural attributes significantly impact the efficacy of drugs.Consequently,delving into the study of solid formulation structures is of paramount importance.This paper employs bibliometrics to summarize references on solid formulations and physical structure over the past 5 years,providing a visual representation through CiteSpace.Additionally,we explore influential factors affecting the structure of solid formulations at three distinct levels:raw material,intermediate,and final product.It delves into the discussion of various characterization techniques employed to analyze the physical structure of solid formulations.The techniques include scanning electron microscopy,transmission electron microscopy,X-ray diffraction,nuclear magnetic resonance,LF-nuclear magnetic resonance,thermal analysis,and terahertz.Emphasis is placed on the significance of investigating formulation structures,serving as a found ational step for future research and development in this field.This comprehensive approach aims to contribute to the understanding and advancement of solid formulations for enhanced drug effectiveness. 展开更多
关键词 Solid formulations physical structure CITESPACE Affecting factors physical characterization
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Single Crystal Growth and Physical Property Characterization of Non-centrosymmetric Superconductor PbTaSe_2 被引量:2
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作者 龙雨佳 赵凌霄 +6 位作者 王培培 杨槐馨 李建奇 子海 任治安 任聪 陈根富 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第3期103-106,共4页
We report on the single crystal growth and superconducting properties of PbTaSe2 with the non-centrosymmetric crystal structure. By using the chemicM vapor transport technique, centimeter-size single crystals are succ... We report on the single crystal growth and superconducting properties of PbTaSe2 with the non-centrosymmetric crystal structure. By using the chemicM vapor transport technique, centimeter-size single crystals are success- fully obtained. The measurement of temperature dependence of electricaJ resistivity p(T) in both normal and superconducting states indicates a quasi-two-dimensional electronic state in contrast to that of polycrystalline samples. Specific heat C(T) measurement reveals a bulk superconductivity with Tc ≈ 3.75K and a specific heat jump ratio of 1.42. All these results are in agreement with a moderately electron-phonon coupled, type-g Bardeen-Cooper-Schrieffer superconductor. 展开更多
关键词 of on in Single Crystal Growth and physical Property characterization of Non-centrosymmetric Superconductor PbTaSe2 IS that for BCS were been HIGH with
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Elaboration and Characterization of Composite Materials Reinforced by Papaya Trunk Fibers (<i>Carica papaya</i>) and Particles of the Hulls of the Kernels of the Winged Fruits (<i>Canarium schweinfurthii</i>) with Polyester Matrix 被引量:1
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作者 Ze Eric Parfait Noah Pierre Marcel +4 位作者 Nnomo Elobi Didine Nfor Clins Wiryikfu Betene Ebanda Fabien Ngahiyi Abbé Claude Valery Atangana Ateba 《Journal of Minerals and Materials Characterization and Engineering》 2020年第5期341-352,共12页
In this work we determine the physical and mechanical properties of local composites reinforced with papaya trunk fibers (FTP) on one hand and particles of the hulls of the kernels of the garlic (PCNFA) in the other h... In this work we determine the physical and mechanical properties of local composites reinforced with papaya trunk fibers (FTP) on one hand and particles of the hulls of the kernels of the garlic (PCNFA) in the other hand. The samples are produced according to BSI 2782 standards;by combining fibers and untreated to polyester matrix following the contact molding method. We notice that the long fibers of papaya trunks improve the tensile/compression characteristics of composites by 45.44% compared to pure polyester;while the short fibers improve the flexural strength of composites by 62.30% compared to pure polyester. Furthermore, adding fibers decreases the density of the final composite material and the rate of water absorption increases with the size of the fibers. As regards composite materials with particle reinforcement from the cores of the winged fruits, the particle size (fine ≤ 800 μm and large ≤ 1.6 mm) has no influence on the Young’s modulus and on the rate of water absorption. On the other hand, fine particles improve the flexural strength of composite materials by 53.08% compared to pure polyester;fine particles increase the density by 19% compared to the density of pure polyester. 展开更多
关键词 physical and Mechanical characterization Composite Fibers Papaya Tree Trunk PARTICLES Shells KERNELS Garlic Fruits
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The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain
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作者 马建华 李剑 千怀遂 《Journal of Geographical Sciences》 SCIE CSCD 2004年第4期437-446,共10页
The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain possess transitional characters evidently in two directions: one is from the western mountain to the eastern ... The features of physical geography in the transitional region between Qinling Mountains and Huanghuai Plain possess transitional characters evidently in two directions: one is from the western mountain to the eastern plain and the other is from southern subtropical zone to northern temperate zone. Torrential rain, especially strong torrential rain is frequent in the transitional region, and there are many torrential rain centers. A majority of torrential rain is distributed among 100-200 m asl. The winter temperature at 100-400 m asl is higher than that in Huanghuai Plain whose altitude is lower than that of the transitional region, and the highest temperature in January appears at 350-400 m asl.The thickness of warm slope belt in the transitional region varies from 100 m to 250 m asl. The formation of torrential rain and warm slope belt is the result of joint action of atmospheric circulation and local terrain. Frequent torrential rains and warm slope belt had tremendous influences on the soil properties, plant distribution and local climate in the transitional region. 展开更多
关键词 qinling mountains huanghuai plain characters of physical geography torrential rain warm slope belt
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Impact of open dumping of municipal solid waste on soil properties in mountainous region 被引量:2
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作者 Anchal Sharma Ashok Kumar Gupta Rajiv Ganguly 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2018年第4期725-739,共15页
This paper presents the effect of open dumping of municipal solid waste(MSW) on soil characteristics in the mountainous region of Himachal Pradesh, India. The solid waste of dumpsite contains various complex character... This paper presents the effect of open dumping of municipal solid waste(MSW) on soil characteristics in the mountainous region of Himachal Pradesh, India. The solid waste of dumpsite contains various complex characteristics with organic fractions of the highest proportions. As leachate percolates into the soil, it migrates contaminants into the soil and affects soil stability and strength. The study includes the geotechnical investigation of dump soil characteristics and its comparison with the natural soil samples taken from outside the proximity of dumpsites. The geochemical analysis of dumpsite soil samples was also carried out by scanning electron microscopy(SEM) and energy dispersive X-ray spectroscopy(EDS).Visual inspection revealed that the MSW consists of high fraction of organics, followed by paper. The soil samples were collected from five trial pits in the dumpsites at depths of 0.5 m, 1 m and 1.5 m. Then the collected soil samples were subjected to specific gravity test, grain size analysis, Atterberg’s limit test,compaction test, direct shear test, California bearing ratio(CBR) test and permeability analysis. The study indicated that the dumpsite soils from four study regions show decreasing trends in the values of maximum dry density(MDD), specific gravity, cohesion and CBR, and increasing permeability as compared to the natural soil. The results show that the geotechnical properties of the soils at all four study locations have been severely hampered due to contamination induced by open dumping of waste. 展开更多
关键词 Municipal solid waste (MSW) physical characterization Soil pollution Open dumping Scanning electron microscopy (SEM) Energy disperse X-ray spectroscopy (EDS)
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Study on the quality of site in the mining district gangue of abandoned place
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作者 卢国斌 李颖 吴祥云 《Journal of Coal Science & Engineering(China)》 2008年第1期73-76,共4页
Being as an example of Fuxin, gangue abandoned place was classified gangue hill and dump. It was built 68 piece of temporary standard fields, which physical and chemical character of soil were researched and analyzed.... Being as an example of Fuxin, gangue abandoned place was classified gangue hill and dump. It was built 68 piece of temporary standard fields, which physical and chemical character of soil were researched and analyzed. The quality of district site was estimated, and five type abandoned place were gotten. Stopping draining cash less than 7 a and draining cash gangue hill was regarded as I gangue hill. Stopping draining gangue age limit 7-15 a and herbage abundance being COlp level was regarded as II gangue hill. Stopping draining gangue age limit 15-25 a and herbage abundance CO2p level was regarded as III gangue hill. Stopping draining cash gangue age limit over 25 a and herbage abundance CO3p level was regarded as IV gangue hill. Dump being formed the underground layer dug up and stacked in the course of mining was regarded asVgangue hill. The results show that every typical abandoned place can plant vegetable. 展开更多
关键词 the quality of site abandoned place physical and chemical character
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Sintering effects on chemical and physical properties of bioactive ceramics
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作者 Lukasz WITEK James SMAY +3 位作者 Nelson R.F.A.SILVA Teja GUDA Joo L.ONG Paulo G.COELHO 《Journal of Advanced Ceramics》 SCIE CAS 2013年第3期274-284,共11页
The objective of this study was to characterize the chemical and physical properties of bioactive ceramics prepared from an aqueous paste containing hydroxyapatite(HA)and beta tri-calcium phosphate(β-TCP).Prior to fo... The objective of this study was to characterize the chemical and physical properties of bioactive ceramics prepared from an aqueous paste containing hydroxyapatite(HA)and beta tri-calcium phosphate(β-TCP).Prior to formulating the paste,HA andβ-TCP were calcined at 800℃and 975℃(11 h),milled,and blended into 15%/85%HA/β-TCP volume-mixed paste.Fabricated cylindrical rods were subsequently sintered to 900℃,1100℃or 1250℃.The sintered specimens were characterized by helium pycnometry,X-ray diffraction(XRD),Fourier transform-infrared(FT-IR),and inductively coupled plasma(ICP)spectroscopy for evaluation of porosity,crystalline phase,functional-groups,and Ca:P ratio,respectively.Mechanical properties were assessed via 3-point bending and diametral compression.Qualitative microstructural evaluation using scanning electron microscopy(SEM)showed larger pores and a broader pore size distribution(PSD)for materials sintered at 900℃and 1100℃,whereas the 1250℃samples showed more uniform PSD.Porosity quantification showed significantly higher porosity for materials sintered to 900℃and 1250℃(p<0.05).XRD indicated substantial deviations from the 15%/85%HA/β-TCP formulation following sintering where lower amounts of HA were observed when sintering temperature was increased.Mechanical testing demonstrated significant differences between calcination temperatures and different sintering regimes(p<0.05).Variation in chemical composition and mechanical properties of bioactive ceramics were direct consequences of calcination and sintering. 展开更多
关键词 bone graft material chemical/physical characterization SINTERING bi-phasic calcium phosphate(BCP)
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Research progress of Fe–N–C catalysts for the electrocatalytic oxygen reduction reaction 被引量:6
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作者 Ying Wang Lei Wang Honggang Fu 《Science China Materials》 SCIE EI CAS CSCD 2022年第7期1701-1722,共22页
The oxygen reduction reaction(ORR)is an important half-reaction for various energy devices,such as fuel cells and metal-air batteries.The sluggish kinetics of the four-electron ORR needs the development of electrocata... The oxygen reduction reaction(ORR)is an important half-reaction for various energy devices,such as fuel cells and metal-air batteries.The sluggish kinetics of the four-electron ORR needs the development of electrocatalysts with high efficiency and activity to replace precious metal platinum.Alternatively,metal±nitrogen±carbon catalysts,particularly Fe±N±C,are considered the most promising candidates because their rich active sites can reduce the energy barrier of oxygenic intermediates.In this review,the recent research breakthroughs of Fe±N±C catalysts in theoretical and experimental studies are summarized in detail.First,the mechanistic understanding of the electrocatalytic ORR based on Fe±N±C catalysts is outlined.Then,the design strategies of Fe±N±C catalysts and classifications of active sites are expounded,after which the connection between the active site and catalytic performance is discussed.Subsequently,the application status of Fe±N±C catalysts in polymer membrane fuel cells and zinc-air batteries is described.Finally,the challenges and opportunities of Fe±N±C catalysts regarding controllable synthesis,mechanism,and applications in energy devices are further proposed. 展开更多
关键词 Fe-N-C catalysts oxygen reaction mechanisms physical characterizations design strategies theoretical calculations fuel cells Zn-air battery
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Comprehensive Evaluation of Powdered Chinese Herbal Medicines-An Exemplification of Isatidis Radix
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作者 Xue Han Ming-quan Wu +8 位作者 Zhi-rui Yang Ding-kun Zhang Yi Mao Jin Han Yin-qiu Huang Yong-feng Zhou Yan-ling Zhao Jia-bo Wang Xiao-he Xiao 《Chinese Herbal Medicines》 CAS 2016年第3期286-292,共7页
Objective Currently, powdered Chinese herbal medicines (CHMs) were mainly evaluated through physical property, chemical dissolution, and bioactivity independently. It could not reflect the quality comprehensively. T... Objective Currently, powdered Chinese herbal medicines (CHMs) were mainly evaluated through physical property, chemical dissolution, and bioactivity independently. It could not reflect the quality comprehensively. This paper was to explore and establish a comprehensive evaluation method for powdered CHMs. Methods Isatidis Radixwas chosen as an exemple. Firstly, powdered Isatidis Radixin different particle size was prepared. Then, their physical properties were characterized. The dissolution of index component epigoitrin was determined, and their antiviral activities were evaluated by neuraminidase-based bioassay. Results As the particle size decreased, powder distribution tended to be uniform, and the dissolution of epigoitrin increased, antiviral activity enhanced. According to cluster analysis of above results, the sequence of evaluation consequence was ultrafine powder S2 (D90:32.80± 0.29) 〉 ultrafine powder S1 (D90:52.08 ± 0.53) 〉 fine powder SO (D90:118.16± 0.76) (from the superior to the inferior). Conclusion Overall, the comprehensive evaluation for powdered CHMs based on the physical characterization, chemical dissolution, and bioassay could not only be used to evaluate powdered herbs, but also guide the screening and optimization of the particle size of powder. 展开更多
关键词 chemical dissolution comprehensive evaluation Isatidis Radi neuraminidase-basedbioassay physical characterization powdered Chinese herbal medicine
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Determination of microcapsule physicochemical, structural, and mechanical properties 被引量:6
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作者 Andrew Gray Stefan Egan +1 位作者 Serafim Bakalis Zhibing Zhang 《Particuology》 SCIE EI CAS CSCD 2016年第1期32-43,共12页
Research into the fundamental properties of microcapsules and use of the results to develop a wide variety of products in industries such as printing, fast-moving consumer goods, construction, pharmaceuticals, and agr... Research into the fundamental properties of microcapsules and use of the results to develop a wide variety of products in industries such as printing, fast-moving consumer goods, construction, pharmaceuticals, and agrochemicals is a dynamic and ever-progressing field of study. For microcapsules to be effective in providing protection from harsh environments or delivering large payloads, it is essential to have a good understanding of their properties to enable quality control during formulation, storage, and applications. This review aims to outline the commonly used techniques for determining the physicochemical, struc- tural, and mechanical properties of microcapsules, and highlights the interlinked nature of these three areas with respect to the end-use industrial application. This review provides information on techniques that are well supported in the literature, and also examines microcapsule analytical techniques that will become more prevalent as a result of new technological developments or extensions from other areas of study. 展开更多
关键词 characterization Chemical composition Experimental technique Mechanical properties Microcapsule physical structure
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