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Optimization of Extraction Process for Total Flavonoids from Penthorum chinense Pursh and Comparison of Their Contents from Different Parts
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作者 Hongsheng LIU Jiqiang YAO +2 位作者 Xue BAI Jianying KANG Yefei YUAN 《Medicinal Plant》 2024年第2期10-14,共5页
[Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experimen... [Objectives]This study was conducted to optimize the extraction process of total flavonoids from Penthorum chinense Pursh and compare their contents from different parts.[Methods]Single factor and orthogonal experiments were designed to optimize the extraction process of total flavonoids from P.chinense Pursh with the volume fraction of ethanol,the ratio of material to liquid,heating reflux extraction time and extraction times as factors,and the content of total flavonoids as the index.A verification test was carried out.The optimized extraction process was adopted to compare the contents of total flavonoids from different parts of P.chinense Pursh.[Results]The best extraction process was extracting the powder of P.chinense Pursh for 2.0 h with 20 times of 55%ethanol by reflux twice.Under this condition,the contents of total flavonoids were 3.63%,8.90%,11.28%,and 4.36%from stems,leaves,flowers and whole grass of P.chinense Pursh,respectively.[Conclusions]The process is reasonable,feasible and stable,and can effectively extract total flavonoids from P.chinense Pursh.The contents of total flavonoids from different parts of P.chinense Pursh were quite different,and the value was higher in the leaves and flowers,so the proportions of leaves and flowers should be paid attention to in the industrial processing of P.chinense Pursh. 展开更多
关键词 Penthorum chinense Pursh Total flavonoids Orthogonal experiments Extraction process Content determination
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Qualitative exploration of home life experiences and care needs among elderly patients with temporary intestinal stomas
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作者 Si-Meng Wang Jian-Ling Jiang +5 位作者 Rui Li Juan-Juan Wang Chun-Hong Gu Jia Zeng Xiao-Hui Wei Mei Chen 《World Journal of Gastroenterology》 SCIE CAS 2024年第22期2893-2901,共9页
BACKGROUND This study employed a phenomenological research approach within qualitative research to explore the challenges encountered by elderly individuals with temporary colostomies in managing their daily lives and... BACKGROUND This study employed a phenomenological research approach within qualitative research to explore the challenges encountered by elderly individuals with temporary colostomies in managing their daily lives and care needs.Protecting the anus surgery combined with temporary colostomy has emerged as a prevalent treatment modality for low rectal cancer.However,the ileostomy is susceptible to peri-stoma skin complications,as well as fluid,electrolyte,and nutritional imbalances,posing challenges to effective management.The successful selfmanagement of patients is intricately linked to their adjustment to temporary colostomy;nonetheless,there remains a dearth of research examining the factors influencing self-care among temporary colostomy patients and the obstacles they confront.AIM To investigate the lived experiences,perceptions,and care requirements of temporary colostomy patients within their home environment,with the ultimate goal of formulating a standardized management protocol.METHODS Over the period of June to August 2023,a purposive sampling technique was utilized to select 12 patients with temporary intestinal stomas from a tertiary hospital in Shanghai,China.Employing a phenomenological research approach,a semi-structured interview guide was developed,and qualitative interviews were conducted using in-depth interview techniques.The acquired data underwent coding,analysis,organization,and summarization following Colaizzi’s seven-step method.RESULTS The findings of this study revealed that the experiences and needs of patients with temporary intestinal stomas can be delineated into four principal themes:Firstly,Temporary colostomy patients bear various burdens and concerns about the uncertainty of disease progression;secondly,patients exhibit limited self-care capabilities and face information deficits,resulting in heightened reliance on healthcare professionals;thirdly,patients demonstrate the potential for internal motivation through proactive self-adjustment;and finally,patients express a significant need for emotional and social support.CONCLUSION Home-living patients with temporary intestinal stomas confront multifaceted challenges encompassing burdens,inadequate self-care abilities,informational deficits,and emotional needs.Identifying factors influencing patients’self-care at home and proposing strategies to mitigate barriers can serve as a foundational framework for developing and implementing nursing interventions tailored to the needs of patients with temporary intestinal stomas. 展开更多
关键词 ELDERLY Temporary intestinal stomas Life experiences Intestinal ostomy complications Qualitative study
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Preclinical Verification of Modulated Electro-Hyperthermia —Part I. In Vitro Research
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作者 Andras Szasz 《International Journal of Clinical Medicine》 CAS 2024年第7期257-298,共42页
Modulated electro-hyperthermia (mEHT) targets tissue’s natural electric and thermal heterogeneities to heat the cancer cells selectively. The applied 13.56 MHz radiofrequency (RF) is a carrier of the low-frequency mo... Modulated electro-hyperthermia (mEHT) targets tissue’s natural electric and thermal heterogeneities to heat the cancer cells selectively. The applied 13.56 MHz radiofrequency (RF) is a carrier of the low-frequency modulation. The high-frequency part was chosen to select the malignant lesion using the specialties of the tumor: the higher conductivity and dielectric constant of the tumor than its host. The electric field selects the tumor, and the low-frequency amplitude modulation polarizes and excites the transmembrane proteins of the malignant cells. The dominant absorption of the energy by the microscopic clusters of the membrane rafts acts like nanoparticle heating. Exciting the membrane produces various apoptotic signals. The processes were modeled using silico and phantom experiments, which proved the concept. The preclinical verification was made in vitro and in vivo, and in the end, clinical proofs validated the method. Our objective is to follow all the development steps from the laboratory to the clinics in a trilogy of articles. This present is the first part, which deals with in silico, phantom, and in vitro research. 展开更多
关键词 Modulated Electro-Hyperthermia mEHT In Silico Calculations Phantom Measurement In Vitro Experiments thermal Effects Nonthermal processes Apoptosis
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Comparison on the Origin and Development of Sophora flavescens in China and Japan
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作者 Jing YAN Zheng FAN +2 位作者 Yuling XU Chenyu ZHOU Rongchun HAN 《Agricultural Biotechnology》 2024年第2期58-63,共6页
Sophora flavescens , which was first recorded in Shen Nong s Herbal Classic , has the functions of clearing away heat, drying dampness, killing parasites and promoting urination. In its long-term application, traditio... Sophora flavescens , which was first recorded in Shen Nong s Herbal Classic , has the functions of clearing away heat, drying dampness, killing parasites and promoting urination. In its long-term application, traditional Chinese medicine has gradually deepened its understanding of the origin and efficacy of S. flavescens . In order to explore changes in the origin and efficacy of traditional Chinese herb S. flavescens in the history of China and Japan, in this paper, the origin and development of S. flavescens in China and Japan were compared from three aspects: the origin, medicinal efficacy, and processing methods of S. flavescens in China and Japan, hoping to provide clear understanding of the medicinal plant S. flavescens . 展开更多
关键词 Sophora flavescens JAPAN Herbalogical study processING
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Family journey in the process of recovery of schizophrenia:A qualitative study
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作者 Sifa FAUZIAH Ummi Malikal BALQIS +2 位作者 Obar OBAR Asep SURYADIN Stefani CHAIRUNISA 《Journal of Integrative Nursing》 2024年第2期83-89,共7页
Objective:The aim of this research is to explore the life experiences of schizophrenic families in accompanying the recovery process.Methods:This study uses a qualitative method with descriptive phenomenology to expla... Objective:The aim of this research is to explore the life experiences of schizophrenic families in accompanying the recovery process.Methods:This study uses a qualitative method with descriptive phenomenology to explain phenomena from family experiences.The number of the participants was eight families who had family members with schizophrenia.Sampling was determined by purposive sampling.Data were collected through in-depth interviews and analyzed using the Colaizzi method.Results:The results of this study show four themes that emerged including(1)psychological burden on the family,(2)families needing support in the recovery process,(3)obstacles due to social stigma,and(4)family gratitude for being able to pass the test patiently.Conclusion:The schizophrenia family’s journey in the recovery process is very long.They are required to endure in assisting the recovery process.Experiences felt by the family include feelings,obstacles,and hopes that arise in carrying out their role to assist the recovery process which aims to improve the health of schizophrenia patients.The findings from this study provide insight for nurses to be able to pay attention to family psychological problems by strengthening families through home visits and health promotion related to the recovery process of survivor schizophrenia. 展开更多
关键词 Family journey life experiences recovery process SCHIZOPHRENIA
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Process Characterization of the Transesterification of Rapeseed Oil to Biodiesel Using Design of Experiments and Infrared Spectroscopy
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作者 Tobias Drieschner Andreas Kandelbauer +1 位作者 Bernd Hitzmann Karsten Rebner 《Journal of Renewable Materials》 SCIE EI 2023年第4期1643-1660,共18页
For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the proc... For optimization of production processes and product quality,often knowledge of the factors influencing the process outcome is compulsory.Thus,process analytical technology(PAT)that allows deeper insight into the process and results in a mathematical description of the process behavior as a simple function based on the most important process factors can help to achieve higher production efficiency and quality.The present study aims at characterizing a well-known industrial process,the transesterification reaction of rapeseed oil with methanol to produce fatty acid methyl esters(FAME)for usage as biodiesel in a continuous micro reactor set-up.To this end,a design of experiment approach is applied,where the effects of two process factors,the molar ratio and the total flow rate of the reactants,are investigated.The optimized process target response is the FAME mass fraction in the purified nonpolar phase of the product as a measure of reaction yield.The quantification is performed using attenuated total reflection infrared spectroscopy in combination with partial least squares regression.The data retrieved during the conduction of the DoE experimental plan were used for statistical analysis.A non-linear model indicating a synergistic interaction between the studied factors describes the reactor behavior with a high coefficient of determination(R^(2))of 0.9608.Thus,we applied a PAT approach to generate further insight into this established industrial process. 展开更多
关键词 process analytical technology TRANSESTERIFICATIon design of experiment attenuated total reflection infrared spectroscopy partial least square regression
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Experimental Analysis on the Development of Cognitive Processes in Childhood Through Body Experience
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作者 Giulia Torregiani Luisa Bonfiglio +1 位作者 Francesco Maria Melchiori Francesco Peluso Cassese 《Psychology Research》 2018年第11期527-543,共17页
This study aims at comparing the effect of an innovative educational approach,based on the continuous relationship between mind and body,to traditional methodologies;more in particular,it focuses on the cognitive proc... This study aims at comparing the effect of an innovative educational approach,based on the continuous relationship between mind and body,to traditional methodologies;more in particular,it focuses on the cognitive processes of language and memory in childhood.Previous studies showed that the Embodiment Theory of Conceptual Representations considers the extent to which the concepts are embodied,i.e.,the way their conceptual features are represented in sensory and motor brain areas in an experience-dependent way.Similarly,the Motor Theory of Language suggests considering phonetic gestures,made by the speaker to produce them as language perception objects,reproduced in the brain as real invariant motor commands.This longitudinal research analyzed the impact of a museum-based education on the memory and language process of children aged 3-6 years,with the purpose of building links between the evolutionary dimension and the didactic dimension.In a wider perspective,these aspects assume great importance for educators that aim to train qualified students,ethically informed and trained as world citizens,starting from neuroscientific discoveries. 展开更多
关键词 UNSTRUCTURED DIDACTICS CHILDHOOD COGNITIVE processes body experience EDUCATIonAL NEUROSCIENCE
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Smoothed particle hydrodynamics modeling and simulation of foundry filling process 被引量:2
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作者 曹文炅 周照耀 蒋方明 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2015年第7期2321-2330,共10页
A numerical model of foundry filling process was established based on the smoothed particle hydrodynamics(SPH)method.To mimic the constraints that the solid mold prescribes on the filling fluid,a composite treatment... A numerical model of foundry filling process was established based on the smoothed particle hydrodynamics(SPH)method.To mimic the constraints that the solid mold prescribes on the filling fluid,a composite treatment to the solid boundaries is elaborately designed.On solid boundary surfaces,boundary particles were set,which exert Lennard-Jones force on approaching fluid particles;inside the solid mold,ghost particles were arranged to complete the compact domain of near-boundary fluid particles.Water analog experiments were conducted in parallel with the model simulations.Very good agreement between experimental and simulation results demonstrates the success of model development. 展开更多
关键词 smoothed particle hydrodynamics foundry filling process composite boundary treatment water analog experiment
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Comparative Study on the Development Levels of Cold Chain Logistics for Agricultural Products between China and Developed Countries Based on Analytic Hierarchy Process 被引量:4
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作者 周兴建 《Agricultural Science & Technology》 CAS 2012年第5期1110-1114,共5页
By introducing the analytic hierarchy process (AHP), a model is constructed to compare the logistics development level of cold chain for agricultural products between China and other developed countries such as Unit... By introducing the analytic hierarchy process (AHP), a model is constructed to compare the logistics development level of cold chain for agricultural products between China and other developed countries such as United States, Japan and Euro- pean. The paper makes a comparative study on the development levels of agricultural cold chain logistics in China and developed countries from the aspects of the level of cold chain logistics facilities and equipments, the degree of cold chain logistics market-oriented and the capacity of cold chain logistics, then determines the problems of cold chain logistics in China. With the experiences learning from developed countries, some countermeasures are proposed to resolve those problems of cold chain logistics for agricultural products development combining with the national conditions in China. 展开更多
关键词 Analytic hierarchy process Agricultural products Cold chain logistics Comparative study
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A Quality Evaluation System for Dissertation Based on Fuzzy Analytic Hierarchy Process
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作者 Kang Xu Zhenhao Zhang +4 位作者 Shuo Wang Yunhui Lv Jiafei Li Xiaodan Cai Yongchun Cui 《Applied Mathematics》 2024年第7期441-454,共14页
A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. T... A dissertation is a research report or scientific paper written by an author to obtain a certain degree. It reflects postgraduates’ research achievements and the educational quality of an institute, even a country. To construct an optimized quality evaluation system for postgraduate dissertation (QESPD), we summarized the influencing factors and invited 10 experienced specialists to rate and prioritize them based on fuzzy analytic hierarchy process. Four primary indicators (innovation, integrity, scientificity and normativity) and 16 sub-indicators were selected to form the evaluation system. The order of primary indicators by weight, was innovation (0.4269), scientificity (0.2807), integrity (0.1728) and normativity (0.1196). The top five sub-dimensions were theoretical originality, scientific value, data reliability, design rationality and evidence credibility. To demonstrate the effectiveness of the proposed system, a case study was performed. In the case study, it was demonstrated that the established two-index-hierarchy QESPD in this study was a more scientific and reasonable evaluation system worthy of promotion and application. 展开更多
关键词 DISSERTATIon Quality Evaluation Indicator System Fuzzy Analytic Hierarchy process Case Study
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Formulation of Work-Study Combined and Result-Oriented Integrated Curriculum Standards
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作者 Lianfang LI Chunhua DU +2 位作者 Fen YANG Yun LI Yanfei NIU 《Medicinal Plant》 2024年第3期79-83,共5页
According to the Annex Technical Regulations for Integrated Curriculum Development(Trial)in Document No.30 of the General Office of the Ministry of Human Resources and Social Security(2012),this paper studies the form... According to the Annex Technical Regulations for Integrated Curriculum Development(Trial)in Document No.30 of the General Office of the Ministry of Human Resources and Social Security(2012),this paper studies the formulation of the curriculum standards for the integration of Chinese medicinal materials production.We focus on the formulation ideas of the curriculum standards for the integration of Chinese medicinal materials production,the formulation process of the curriculum standards for the integration of Chinese medicinal materials production,including the description of typical work tasks,the determination of curriculum objectives,the analysis of study content,the description of referential study tasks,teaching implementation suggestions,assessment and evaluation suggestions,which can provide a reference for the development and research of other related integrated courses. 展开更多
关键词 Integration of WORK and STUDY WORK process Curriculum STANDARDS Production of Chinese MEDICINAL materials Typical WORK TASKS REFERENTIAL STUDY TASKS
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Experimental Study on the Treatment of Tertiary Oil Recovery Wastewater via a Novel Electro-Coagulation Method
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作者 Wei Cui Zhilun Yan +3 位作者 Zhi Tang Mengyao Xu Jian Tian Chengyi Shen 《Fluid Dynamics & Materials Processing》 EI 2023年第1期51-60,共10页
At present,methods for treating tertiary oil recovery wastewater via electro-coagulation are still in their early stage of development.In this study,a device for electro-coagulation wastewater treatment was built and ... At present,methods for treating tertiary oil recovery wastewater via electro-coagulation are still in their early stage of development.In this study,a device for electro-coagulation wastewater treatment was built and tested in an oil field.The effects that the initial pH value,electrode type,and connection mode have on the coagulation and separation effect were assessed by measuring the mass fraction and turbidity of oil.The results have shown that when the electro-coagulation method is used,the effectiveness of the treatment can be significantly increased in neutral pH conditions(pH=7),in acidic conditions,and in alkaline conditions.Compared to an Al electrode,the floc that is produced by an Fe electrode is smaller;thus,it does not easily coagulate and settle in a short time.Using the oil removal rate,turbidity removal rate and energy consumption as a basis to assess the performances,the results have demonstrated that the combined aluminum alloy iron composite electrode should be used as electrolytic electrode. 展开更多
关键词 ELECTROCOAGULATIon oily sewage POLYMER experiment study
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Offshore Software Maintenance Outsourcing Process Model Validation:A Case Study Approach
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作者 Atif Ikram Masita Abdul Jalil +3 位作者 Amir Bin Ngah Adel Sulaiman Muhammad Akram Ahmad Salman Khan 《Computers, Materials & Continua》 SCIE EI 2023年第3期5035-5048,共14页
The successful execution and management of Offshore Software Maintenance Outsourcing(OSMO)can be very beneficial for OSMO vendors and the OSMO client.Although a lot of research on software outsourcing is going on,most... The successful execution and management of Offshore Software Maintenance Outsourcing(OSMO)can be very beneficial for OSMO vendors and the OSMO client.Although a lot of research on software outsourcing is going on,most of the existing literature on offshore outsourcing deals with the outsourcing of software development only.Several frameworks have been developed focusing on guiding software systemmanagers concerning offshore software outsourcing.However,none of these studies delivered comprehensive guidelines for managing the whole process of OSMO.There is a considerable lack of research working on managing OSMO from a vendor’s perspective.Therefore,to find the best practices for managing an OSMO process,it is necessary to further investigate such complex and multifaceted phenomena from the vendor’s perspective.This study validated the preliminary OSMO process model via a case study research approach.The results showed that the OSMO process model is applicable in an industrial setting with few changes.The industrial data collected during the case study enabled this paper to extend the preliminary OSMO process model.The refined version of the OSMO processmodel has four major phases including(i)Project Assessment,(ii)SLA(iii)Execution,and(iv)Risk. 展开更多
关键词 offshore outsourcing process model model validation vendor challenges case study
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Development of Preparation Systems with K_2CsSb Photocathodes and Study on the Preparation Process 被引量:3
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作者 Fan Zhang Xiao-Ping Li Xiao-Shen Li 《Chinese Physics Letters》 SCIE CAS CSCD 2019年第2期8-11,共4页
The next generation of advanced light sources requires photons with large average flux and high brightness,which needs advanced electron gun matched with excellent photocathode materials. K_2CsSb photocathode has the ... The next generation of advanced light sources requires photons with large average flux and high brightness,which needs advanced electron gun matched with excellent photocathode materials. K_2CsSb photocathode has the advantages of high quantum efficiency, long lifetime and instantaneous response. This study introduces the design of a set of K_2CsSb photocathode preparation systems and detailed preparation process of K_2CsSb photocathodes, including sequential deposition process and co-deposition process, and finally develops a K_2CsSb photocathode. The influence of laser power on the quantum efficiency is also investigated. 展开更多
关键词 CS SB St DEVELOPMENT of PREPARATIon Systems with K2CsSb PHOTOCATHODES and STUDY on the PREPARATIon process
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Modeling study on the flow patterns of gas–liquid flow for fast decarburization during the RH process 被引量:2
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作者 Yi-hong Li Yan-ping Bao +2 位作者 Rui Wang Li-feng Ma Jian-sheng Liu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第2期153-163,共11页
A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained d... A water model and a high-speed video camera were utilized in the 300-t RH equipment to study the effect of steel flow patterns in a vacuum chamber on fast decarburization and a superior flow-pattern map was obtained during the practical RH process. There are three flow patterns with different bubbling characteristics and steel surface states in the vacuum chamber: boiling pattern(BP), transition pattern(TP), and wave pattern(WP). The effect of the liquid-steel level and the residence time of the steel in the chamber on flow patterns and decarburization reaction were investigated, respectively. The liquid-steel level significantly affected the flow-pattern transition from BP to WP, and the residence time and reaction area were crucial to evaluate the whole decarburization process rather than the circulation flow rate and mixing time. A superior flow-pattern map during the practical RH process showed that the steel flow pattern changed from BP to TP quickly, and then remained as TP until the end of decarburization. 展开更多
关键词 modeling study flow pattern vacuum chamber residence time decarburization RH process
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Time consumption, productivity, and cost analysis of the motor manual tree felling and processing in the Hyrcanian Forest in Iran
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作者 Rostam Mousavi Mehrdad Nikouy Jori Uusitalo 《Journal of Forestry Research》 SCIE CAS CSCD 2011年第4期665-669,共5页
An empirical time study was cohducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran's Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree... An empirical time study was cohducted to evaluate the performance of the current felling and tree processing methods used in Northern Iran's Hyrcanian forest. Motor-manual felling is done mostly in winter, while tree processing starts when the felling season ends. We identified the elements of felling and processing work phases, and 142 cycles and 110 cycles were respectively recorded for felling and processing. On the basis of data analysis (time study), we developed statistical models of effective time consumption in the respective work phase and for its total productivity. The production rate of felling with and without delay time was 9.7 and 11.65 trees per hour (0.17 USD.m^-3 and 0.21 USD-m^-3), and the average production cost with and without delay was 1.21 USD and 1.45 USD per tree, respectively. The average productivity of processing was 35 m^3 per effective hour and the average unit cost of processing was 0.92 USD.m^-3. 展开更多
关键词 Motor-manual felling time study CHAINSAW processING cost forest work study
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Comparison of the Results in CO_2 Sequestration Field Experience and Laboratory Studies
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作者 Lijiang Duan,Shuheng Tang School of Energy Resources,China University of Geosciences(Beijing),Beijing 100083,China. 《地学前缘》 EI CAS CSCD 北大核心 2009年第S1期153-153,共1页
Sequestration of carbon dioxide(CO<sub>2</sub>) in deep, unminable coalseam is an innovative technology, because it can not only reduce greenhouse gas in the atmosphere,but also enhance coalbed methane r... Sequestration of carbon dioxide(CO<sub>2</sub>) in deep, unminable coalseam is an innovative technology, because it can not only reduce greenhouse gas in the atmosphere,but also enhance coalbed methane recovery(CO<sub>2</sub>-ECBM).Lots of research have been carried out on this topic in recent years.However,few of them were focused on the comparison of the 展开更多
关键词 CO2 SEQUESTRATIon ECBM FIELD experience LABORATORY study
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Experimental studies of focal mechanism based on the dynamic process of energy release
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作者 郑熙铭 高后秀 +2 位作者 杨渝钦 杨敬宇 李志雄 《Acta Seismologica Sinica(English Edition)》 CSCD 1997年第3期113-118,共6页
ExperimentalstudiesoffocalmechanismbasedonthedynamicprocesofenergyreleaseXIMINGZHENG1)(郑熙铭)HOUXIUGAO2)(高后秀)Y... ExperimentalstudiesoffocalmechanismbasedonthedynamicprocesofenergyreleaseXIMINGZHENG1)(郑熙铭)HOUXIUGAO2)(高后秀)YUQINYANG2)(杨渝... 展开更多
关键词 seismic mechanism dynamic process SIMILARITY experimental study
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The Process of TiB_2-Cu Composite Phase and Structure Formation during Combustion Synthesis
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作者 徐强 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2006年第4期113-116,共4页
The reaction process of combustion synthesis for TiB2 -Cu was investigated in detail using combustion-wave arresting experiment, X-ray diffraction ( XRD ) analysis, SEM analysis and differential thermal analysis ( ... The reaction process of combustion synthesis for TiB2 -Cu was investigated in detail using combustion-wave arresting experiment, X-ray diffraction ( XRD ) analysis, SEM analysis and differential thermal analysis ( DTA ). The XRD analysis results for the different parts of the quenched specimen show that TiCux intermetallic phase firstly forms with the propagation of combustion wave, and then Ti1.87 B50 and Ti3B4 metastable phases come forth due to the diffusion of B atoms and finally the stable TiB2 phase forms because of the continuous diffusion of B atoms. The formation of TiB2 phase is uot completed by one step, but undergoes several transient processes. The process of reaction synthesis for Ti-B-Cu ternary system can be divided into three main stages: melting of Cu and Ti , and the formation of Cu- Ti melt and few TiCux , TiBx intermetallic phases ; large numbers of TiCux intermetallic phases formation and some fine TiB2 particles precipitation ; and the TiB2 particles coarsening and the stable TiB2 and Cu two phases formation in the final product. 展开更多
关键词 combustion synthesis reaction process TiB2 phase combustion-wave arresting experiment
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NMR STUDY ON THE CONFORMATION CHANGE IN THE AGGREGATION PROCESSES OF 1,3-DI(α-NAPHTHYL)PROPANE AND DI(α-NAPHTHYLMETHYL)ETHER
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作者 Rui Qsing XIE Zi Zhong LI You Cheng LIU and Xue Gong LEI (National Laboratory of Applied Organic Chemistry,Lanzhou Uniersity, Lenzhou 730O00) 《Chinese Chemical Letters》 SCIE CAS CSCD 1994年第12期1049-1050,共2页
NMR study on the conformation change in the aggregation process of the titled compounds is reported in this letter.
关键词 DI NAPHTHYL PROPANE STUDY ConFORMATIon the processES AND NMR AGGREGATIon
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