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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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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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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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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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Sedimentary characteristics and internal architecture of a river-dominated delta controlled by autogenic process:implications from a flume tank experiment 被引量:3
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作者 Wen-Jie Feng Chang-Min Zhang +5 位作者 Tai-Ju Yin Yan-Shu Yin Jun-Ling Liu Rui Zhu Qing-Hai Xu Zhe Chen 《Petroleum Science》 SCIE CAS CSCD 2019年第6期1237-1254,共18页
Autogenic processes are widely found in various sedimentary systems and they play an important role in the depositional evolution and corresponding sedimentary architecture.However,autogenic processes are often affect... Autogenic processes are widely found in various sedimentary systems and they play an important role in the depositional evolution and corresponding sedimentary architecture.However,autogenic processes are often affected by changing allogenic factors and are difficult to be identified and analyzed from modern and ancient records.Through the flume tank experiment under constant boundary conditions,the depositional process,evolution principles,and the sedimentary architecture of a river-dominated delta was presented,and a corresponding sedimentary architecture model was constructed.The evolution of river-dominated delta controlled only by autogenic process is obviously periodic,and each autogenic cycle can be divided into an initial progradational stage,a middle retrogratational stage,and a late aggradational–progradational stage.In the initial progradational stage,one feeder channel incised into the delta plain,mouth bar(s)was formed in front of the channel mouth,and small-scale crevasse splays were formed on the delta plain.In the middle retrogradational stage,the feeder channel was blocked by the mouth bar(s)which grew out of water at the end of the initial stage,and a set of large-scale distributary splay complexes were formed on the delta plain.These distributary splay complexes were retrogradationally overlapped due to the continuous migration of the bifurcation point of the feeder channel.In the late aggradational–progradational stage,the feeder channel branched into several radial distributary channels,overlapped distributary channels were formed on the delta plain,and terminal lobe complexes were formed at the end of distributary channels.The three sedimentary layers formed in the three stages constituted an autogenic succession.The experimental delta consisted of six autogenic depositional successions.Dynamic allocation of accommodation space and the following adaptive sediments filling were the two main driving factors of the autogenic evolution of deltas. 展开更多
关键词 River-dominated delta Autogenic process Depositional process Sedimentary architecture Flume tank experiment
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Simulation Experiments of Land Surface Physical Processes and Ecological Effect over Different Underlying Surface 被引量:1
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作者 LIU Shu-hua~(1,2), JIANG Hao-yu, HU Fei~2 LIU Hui-zhi~2 LIANG Fu-ming~1, WANG Jiang-hua~1(1. Group of Atmosphere Boundary Layer and turbulence, Ministry Laboratory of Storm and Drought Flood Damage, Department of Atmospheric Sciences the School of Physics Peking University, Beijing 100871, China 2. State Key Laboratories of Atmosphere Physics and Chemistry, Institute of Atmospheric Physics, Chinese Academy of Science, Beijing 100029, China) 《地球科学进展》 CAS CSCD 2004年第S1期15-20,共6页
Based on the existing Land Surface Physical Process Models(Deardorff, Dickinson, LIU, Noilhan, Seller, ZHAO), a Comprehensive Land Surface Physical Process Model (CLSPPM) is developed by considering the different phys... Based on the existing Land Surface Physical Process Models(Deardorff, Dickinson, LIU, Noilhan, Seller, ZHAO), a Comprehensive Land Surface Physical Process Model (CLSPPM) is developed by considering the different physical processes of the earth's surface-vegetation-atmosphere system more completely. Compared with SiB and BATS, which are famous for their detailed parameterizations of physical variables, this simplified model is more convenient and saves much more computation time. Though simple, the feas... 展开更多
关键词 Comprehensive land surface Physical process model (CLSPPM) Simulation experiment Land surface physical process Ecological effect.
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A continuous and high-efficiency process to separate coal bed methane with porous ZIF-8 slurry:Experimental study and mathematical modelling 被引量:7
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作者 Wan Chen Xiaonan Guo +10 位作者 Enbao Zou Mengling Luo Mengzijing Chen Mingke Yang Hai Li Chongzhi Jia Chun Deng Changyu Sun Bei Liu Lanying Yang Guangjin Chen 《Green Energy & Environment》 SCIE CSCD 2020年第3期347-363,共17页
Coal bed methane has been considered as an important energy resource.One major difficulty of purifying coal bed methane comes from the similar physical properties of CH_4 and N_2.The ZIF-8/water-glycol slurry was used... Coal bed methane has been considered as an important energy resource.One major difficulty of purifying coal bed methane comes from the similar physical properties of CH_4 and N_2.The ZIF-8/water-glycol slurry was used as a medium to separate coal bed methane by fluidifying the solid adsorbent material.The sorption equilibrium experiment of binary mixture(CH_4/N_2)and slurry was conducted.The selectivity of CH_4 to N_2 is within the range of 2-6,which proved the feasibility of the slurry separation method.The modified Langmuir equation was used to describe the gas-slurry phase equilibrium behavior,and the calculated results were in good agreement with the experimental data.A continuous absorption-adsorption and desorption process on the separation of CH_4/N_2 in slurry is proposed and its mathematical model is also developed.Sensitivity analysis is conducted to determine the operation conditions and the energy performance of the proposed process was also evaluated.Feed gas contains 30 mol%of methane and the methane concentration in product gas is 95.46 mol%with the methane recovery ratio of 90.74%.The total energy consumption for per unit volume of product gas is determined as 1.846 kWh Nm^(-3).Experimental results and process simulation provide basic data for the design and operation of pilot and industrial plant. 展开更多
关键词 Coal bed methane Gas separation Phase equilibrium experiment Mathematical model process simulation
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Modeling and optimization of cooling slope process parameters for semi-solid casting of A356 Al alloy 被引量:2
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作者 Hamed KHOSRAVI Reza ESLAMI-FARSANI Mohsen ASKARI-PAYKANI 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第4期961-968,共8页
Semi-solid processing (SSP) of A356 aluminum alloy was discussed via cooling slope (CS) method. The D-optimal design of experiment (DODE) was employed for experimental design and analysis of results. 38 random e... Semi-solid processing (SSP) of A356 aluminum alloy was discussed via cooling slope (CS) method. The D-optimal design of experiment (DODE) was employed for experimental design and analysis of results. 38 random experiments obtained by software were carried out. In experimental stage, the molten aluminum alloy was poured on an inclined plate with different lengths of 100, 300 and 500 mm set at 30°, 45° and 60° of slope angles respectively. Three different pouring temperatures of 660, 680 and 700 ℃ were also used. After the casting process, the partial re-melting treatment was carried out at 590 ℃ for different isothermal time of 5, 8 or 12 min. The combined effect of these factors on globularity of the primary α(Al) crystals was investigated and optimized using DODE. The results indicated that the primary dendritic phase in the conventionally cast A356 alloy was transformed into a non-dendritic one in ingots cast over a cooling plate. The CS processed samples exhibited a globular structure only after re-heating to semi-solid region. The optimum values of pouring temperature, cooling length, slope angle and isothermal holding time were found to be 660 ℃, 360 mm, 48°, and 9 min, respectively. In this case, the globularity of primary crystals was obtained, about 0.91. The obtained model is highly significant with a correlation coefficient of 0.9860. 展开更多
关键词 vA356 aluminum alloy cooling slope process MODELING D-optimal design of experiment
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Optimization of Quality Control Method and Ethanol Extraction Process of Psoralen and Bergapten in Ficus pandurata 被引量:1
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作者 Weiwen PENG Chang CHEN +2 位作者 Weibo DAI Yangcun LU Yingjing WANG 《Medicinal Plant》 CAS 2020年第3期51-54,59,共5页
[Objectives]To establish a qualitative identification and content determination method for psoralen and bergapten in the roots and leaves of Ficus pandurata,and the multi-indicator scoring method to optimize the ethan... [Objectives]To establish a qualitative identification and content determination method for psoralen and bergapten in the roots and leaves of Ficus pandurata,and the multi-indicator scoring method to optimize the ethanol extraction process for the effective parts of F.pandurata.[Methods]Qualitative identification was carried out by thin-layer chromatography(TLC)and content determination was made by high-performance liquid chromatography(HPLC);the content of psoralen and bergapten and extract yield were used as indicators,to investigate the effects of ethanol volume fraction,solid-to-liquid ratio,extraction time and extraction times on the ethanol extraction process of F.pandurata;multi-indicator scoring method was adopted,orthogonal test method was designed to optimize the extraction process,and verification test was performed.[Results]TLC chart of F.pandurata shows clear spots and good separation;the detected concentrations of psoralen and bergapten in the roots are in the range of 1.02-32.64μg/mL and shows a good linear relationship with the peak area(r=0.9997);these components have not been detected in the leaves,and the precision,RSD of stability and repeatability test is less than 2%;the average recovery rate was 99.8%-100.2%,and the RSD value is 1.12%-1.13%(n=6);the optimized extraction process is to use 50%ethanol as the extraction solvent,the solid-to-liquid ratio of 1∶10,reflux extraction of 3 times,and 1.5 h each time;the results of the three batches of verification tests show that the content of the two indicator components obtained is high,and the average value of the total amount is 0.34 mg/g(RSD=0.30%,n=3).[Conclusions]The established quality control method for F.pandurata is simple,easy,accurate and reproducible;the preferred extraction process is stable and feasible,suitable for the extraction and purification of coumarin effective parts in F.pandurata roots,so it is expected to provide references for further development of F.pandurata. 展开更多
关键词 Ficus pandurata Hance Quality control Extraction process Orthogonal experiment Multi-indicator scoring method
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Applying a modified conduit flow process to understand conduit-matrix exchange of a karst aquifer 被引量:1
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作者 Liang-jie Zhao Yang Yang +3 位作者 Jian-wen Cao Zhe Wang Song Luan Ri-yuan Xia 《China Geology》 2022年第1期26-33,共8页
Due to the high heterogeneity and complexity of water flow movement for multiple karst water-bearing mediums,the evaluation,effective development,and utilization of karst water resources are significantly limited.Matr... Due to the high heterogeneity and complexity of water flow movement for multiple karst water-bearing mediums,the evaluation,effective development,and utilization of karst water resources are significantly limited.Matrix flow is usually laminar,whereas conduit flow is usually turbulent.The driving mechanisms of water exchange that occur between the karst conduit and its adjacent matrix are not well understood.This paper investigates the hydrodynamic characteristics and the mechanism of flow exchange in dual water-bearing mediums(conduit and matrix)of karst aquifers through laboratory experimentation and numerical simulation.A karst aquifer consisting of a matrix network and a conduit was proposed,and the relationship between the water exchange flux and hydraulic head differences generated from the laboratory experiments was analyzed.Two modes of experimental tests were performed with different fixed water level boundaries in the laboratory karst aquifer.The results indicate that the water exchange capacity was proportional to the square root of hydraulic head differences.The linear exchange term in the conduit flow process(CFP)source program was modified according to experimental results.The modified CFP and the original CFP model experimental data results were compared,and it was found that the modified CFP model had better fitting effects.These results showed that the water exchange mechanism between conduit and matrix is very important for solid-liquid interface reaction,water resource evaluation,and understanding of karst hydrodynamic behavior. 展开更多
关键词 CONDUIT Matrix Conduit flow process(CFP)model Karst aquifer Laboratory experiment Water exchange Hydrogelogical survey engineering
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Anterior transhepatic approach for total caudate lobectomy including spigelian lobe,paracaval portion and caudate process:A Brazilian experience 被引量:1
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作者 Eduardo de Souza Martins Fernandes Carlo Alberto Pacilio +3 位作者 Felipe Pedreira Tavares de Mello Ronaldo de Oliveira Andrade Leandro Moreira Savattone Pimentel Camila Liberato Girão 《Hepatobiliary & Pancreatic Diseases International》 SCIE CAS CSCD 2018年第4期371-373,共3页
To the Editor:Nowadays,because of the infiltration of cholangiocarcinoma to the parenchyma and/or bile ducts of the caudate lobe,the inclusion of caudate lobe combined with a major hepatectomy remains the gold standar... To the Editor:Nowadays,because of the infiltration of cholangiocarcinoma to the parenchyma and/or bile ducts of the caudate lobe,the inclusion of caudate lobe combined with a major hepatectomy remains the gold standard approach for a resectable hilar cholangiocarcinoma.Since the last years of the 20th century,some authors have begun to report isolated caudate lobe resection for hepatocellular 展开更多
关键词 HCC Anterior transhepatic approach for total caudate lobectomy including spigelian lobe paracaval portion and caudate process:A Brazilian experience
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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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Combining the People Power and the Process Power to Achieve Six Sigma Process Capability——A Case Study
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作者 G Srinivasan N Srinivasa Gupta 《厦门大学学报(自然科学版)》 CAS CSCD 北大核心 2002年第S1期251-,共1页
Achieving Six-Sigma process capability starts with l istening to the Voice of the Customers, and it becomes a reality by combining th e People Power and the Process Power of the organisation. This paper presents a Six... Achieving Six-Sigma process capability starts with l istening to the Voice of the Customers, and it becomes a reality by combining th e People Power and the Process Power of the organisation. This paper presents a Six-Sigma implementation case study carried out in a magnet manufacturing compa ny, which produces bearing magnets to be used in energy meters. If the thickness of the produced bearing magnets is between 2.35 mm and 2.50 mm, they will be ac cepted by the customers. All the time the company could not produce the bearing magnets within the specified thickness range, as their process distribution was flat with 2.20 mm as lower control limit and 2.60 mm as upper control limit. This resulted in a huge loss in the form of non-conformities, loss of time and goodwill. The process capability of the company then was around 0.40. Organisat ion restructuring was carried out to reap the benefit of the People Power of the organisation. Statistically designed experiments (Taguchi Method based Design o f Experiments), Online quality control tools (Statistical Process Control To ols) were effectively used to complete the DMAIC (Define, Measure, Analyse, Impr ove and Control) cycle to reap the benefit of the Process Power of the organisat ion. Presently the company enjoys a process capability of 1.75, a way towards Si x-Sigma Process Capability. 展开更多
关键词 six-sigma process capability people power proc ess power statistically designed experiments online quality control tools
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Resiliency Process and Political Socialization among Palestinian Children Exposed to Political Traumatic Experience: An Integrative Review
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作者 Lobna Harazneh Ayman Hamdan-Mansour 《Open Journal of Nursing》 2019年第3期303-312,共10页
Background: Political conflicts and wars all over the world are global concerns which directly influence the lives of people including children. Over one billion children worldwide inhabit countries or territories tor... Background: Political conflicts and wars all over the world are global concerns which directly influence the lives of people including children. Over one billion children worldwide inhabit countries or territories torn apart by armed conflict, war, or terrorism. Purpose: The purpose of this review was to identify the best evidence on the Resiliency Process and Political Socialization among Palestinian Children Exposed to Political Traumatic Experience. Methods: An integrative review was used to assess the resiliency process and political socialization among Palestinian Children Exposed to Political Traumatic Experience. Data search was between 2009 and 2019 using ProQuest, Nursing Journal Publications, EBSCO, Jordanian Database for Nursing Research, WHO online library, scholar Google scholar, science direct, and PubMed. A total of 8 articles met the eligibility criteria. Results: The eight reviewed articles adopted descriptive analytic and cross-sectional studies. Themes were: Impact of psychological trauma on children, Political socialization process and Resiliency among children. Conclusion: Reviewed articles regarding children reaction to trauma and resiliency process showed that children varied in their responses. The studies showed that children were vulnerable to psychological harms and consequences of trauma that might include PTSD and others behavioral problems. At the same time, the studies confirmed that despite the harmful consequences they had positive adaptation and abilities to resist. 展开更多
关键词 Resiliency process POLITICAL SOCIALIZATION PALESTINIAN CHILDREN POLITICAL TRAUMATIC Experience
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Drying Technology and Formation Process of Naomai Xingshen Capsules
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作者 Congyan ZENG Yu ZHANG +2 位作者 Bin ZHUO Shi LIANG Yuliang HU 《Medicinal Plant》 CAS 2022年第2期8-11,共4页
[Objectives]To optimize the drying technology and formation process of Naomai Xingshen Capsules.[Methods]The yield of paste powder and moisture content as evaluation indicators were taken as indicators,the relative de... [Objectives]To optimize the drying technology and formation process of Naomai Xingshen Capsules.[Methods]The yield of paste powder and moisture content as evaluation indicators were taken as indicators,the relative density of feed liquid,inlet air temperature and dosage of excipients were selected as investigation factors,the orthogonal experiment method was used to optimize the spray drying process.The moisture absorption rate and angle of repose were taken as evaluation indicators,the types of forming excipient were screened,and the critical relative humidity was determined.[Results]The optimum spray drying process was that the relative density of liquid medicine was 1.05(60℃),the air inlet temperature was 200℃,and the dosage of excipients was 2%.The effect of using dextrin as a forming excipient was better,and the relative humidity of the production environment should be controlled below 65%.[Conclusions]The optimized process is stable,feasible,scientific and reasonable,and can be used for large-scale industrial production. 展开更多
关键词 Naomai Xingshen Capsules Orthogonal experiment SPRAY-DRYING Forming process Angle of repose Moisture absorption rate Critical relative humidity
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Simulation Experimental Study on Hydrodynamics Process of Erosion and Sediment by Runoff in Grassland
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作者 XING En-de CUI Wei +1 位作者 LIU Yan-ping LI Jin-rong 《Meteorological and Environmental Research》 2012年第9期66-68,共3页
[Objective]The aim was to study the simulation test of hydrodynamics process of erosion.[Method]Through the runoff scouring experiment,the property of soil erosion in Damaoqi grassland in Inner Mongolia was studied.Th... [Objective]The aim was to study the simulation test of hydrodynamics process of erosion.[Method]Through the runoff scouring experiment,the property of soil erosion in Damaoqi grassland in Inner Mongolia was studied.The process and mechanism of soil erosion were studied.[Result]The results of runoff scouring experiment on inner Damaoqi steppe showed that the mean flow velocity of change slope increased with the discharge of flow and slope gradient.The mean silt content rate,the mean sediment transport rate and the mean sheer stress all increased when the discharge of flow increased,which changed in parabolic form with the increase of slope gradient and the critical gradient is 25°.The relationship between the mean sediment transport rate and the mean sheer stress was linear.[Conclusion]The study provided theoretic basis for the report of soil erosion in grassland in China. 展开更多
关键词 Runoff scouring Grassland steppe Sand process Simulation experiment China
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TIBETAN PLATEAU FIELD EXPERIMENT(TIPEX)AND STUDY ON THE IMPACT OF PHYSICAL PROCESSES OVER TIBETAN PL
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作者 陈联寿 《中国气象科学研究院年报》 1995年第0期1-6,共6页
TIBETANPLATEAUFIELDEXPERIMENT(TIPEX)ANDSTUDYONTHEIMPACTOFPHYSICALPROCESSESOVERTIBETANPLATEAUONGLOBALCLIMATEA... TIBETANPLATEAUFIELDEXPERIMENT(TIPEX)ANDSTUDYONTHEIMPACTOFPHYSICALPROCESSESOVERTIBETANPLATEAUONGLOBALCLIMATEANDDISASTROUSWEATH... 展开更多
关键词 IMPACT OVER PLATEAU and OF ON EXPERIMENT PHYSICAL FIELD processES
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An Experimental Investigation into the Amalgamated Al2O3-40% TiO2 Atmospheric Plasma Spray Coating Process on EN24 Substrate and Parameter Optimization Using TLBO
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作者 Thankam Sreekumar Rajesh Ravipudi Venkata Rao 《Journal of Materials Science and Chemical Engineering》 2016年第6期51-65,共15页
Surface coating is a critical procedure in the case of maintenance engineering. Ceramic coating of the wear areas is of the best practice which substantially enhances the Mean Time between Failure (MTBF). EN24 is a co... Surface coating is a critical procedure in the case of maintenance engineering. Ceramic coating of the wear areas is of the best practice which substantially enhances the Mean Time between Failure (MTBF). EN24 is a commercial grade alloy which is used for various industrial applications like sleeves, nuts, bolts, shafts, etc. EN24 is having comparatively low corrosion resistance, and ceramic coating of the wear and corroding areas of such parts is a best followed practice which highly improves the frequent failures. The coating quality mainly depends on the coating thickness, surface roughness and coating hardness which finally decides the operability. This paper describes an experimental investigation to effectively optimize the Atmospheric Plasma Spray process input parameters of Al<sub>2</sub>O<sub>3</sub>-40% TiO<sub>2</sub> coatings to get the best quality of coating on EN24 alloy steel substrate. The experiments are conducted with an Orthogonal Array (OA) design of experiments (DoE). In the current experiment, critical input parameters are considered and some of the vital output parameters are monitored accordingly and separate mathematical models are generated using regression analysis. The Analytic Hierarchy Process (AHP) method is used to generate weights for the individual objective functions and based on that, a combined objective function is made. An advanced optimization method, Teaching-Learning-Based Optimization algorithm (TLBO), is practically utilized to the combined objective function to optimize the values of input parameters to get the best output parameters. Confirmation tests are also conducted and their output results are compared with predicted values obtained through mathematical models. The dominating effects of Al<sub>2</sub>O<sub>3</sub>-40% TiO<sub>2</sub> spray parameters on output parameters: surface roughness, coating thickness and coating hardness are discussed in detail. It is concluded that the input parameters variation directly affects the characteristics of output parameters and any number of input as well as output parameters can be easily optimized using the current approach. 展开更多
关键词 Atmospheric Plasma Spray (APS) EN24 Design of Experiments (DOE) Teaching Learning Based Optimization (TLBO) Analytic Hierarchy process (AHP) Al2O3-40% TiO2
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Wind tunnel simulation of wind erosion and dust emission processes,and the influences of soil texture
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作者 Xiaofeng Zuo Chunlai Zhang +3 位作者 Xiaoyu Zhang Rende Wang Jiaqi Zhao Wenping Li 《International Soil and Water Conservation Research》 SCIE CSCD 2024年第2期455-466,共12页
Dust emission caused by wind erosion of soil is an important surface process in arid and semi-arid regions.However,existing dust emission models pay insufficient attention to the impacts of aerodynamic entrainment of ... Dust emission caused by wind erosion of soil is an important surface process in arid and semi-arid regions.However,existing dust emission models pay insufficient attention to the impacts of aerodynamic entrainment of particles.In addition,studies of wind erosion processes do not adequately account for the dynamics of wind erosion rates and dust emission fluxes,or for the impact of soil texture on dust emission.Our wind tunnel simulations of wind erosion and dust emission showed that the soil texture,wind erosion duration,and shear velocity are major factors that affect the dynamics of wind erosion and dust emission.Because of the limited supply of surface sand and the change in surface erosion resistance caused by surface coarsening during erosion,the wind erosion rate and the flux of particles smaller than 10μm(PM_(10))caused by aerodynamic entrainment decreased rapidly with increasing erosion duration,which suggests that surface wind erosion and dust emission occur primarily during the initial stage of wind erosion.The PM_(10) emission efficiency decreased with increasing shear velocity following a power function,and finer textured sandy loam soils had greater PM_(10) emission efficiency than loamy sand soils. 展开更多
关键词 Soil texture Wind erosion rate Dust emission efficiency Dynamic process Wind tunnel experiment Shear velocity
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Multi-objective optimization for leaching process using improved two-stage guide PSO algorithm 被引量:8
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作者 胡广浩 毛志忠 何大阔 《Journal of Central South University》 SCIE EI CAS 2011年第4期1200-1210,共11页
A mathematical mechanism model was proposed for the description and analysis of the heat-stirring-acid leaching process.The model is proved to be effective by experiment.Afterwards,the leaching problem was formulated ... A mathematical mechanism model was proposed for the description and analysis of the heat-stirring-acid leaching process.The model is proved to be effective by experiment.Afterwards,the leaching problem was formulated as a constrained multi-objective optimization problem based on the mechanism model.A two-stage guide multi-objective particle swarm optimization(TSG-MOPSO) algorithm was proposed to solve this optimization problem,which can accelerate the convergence and guarantee the diversity of pareto-optimal front set as well.Computational experiment was conducted to compare the solution by the proposed algorithm with SIGMA-MOPSO by solving the model and with the manual solution in practice.The results indicate that the proposed algorithm shows better performance than SIGMA-MOPSO,and can improve the current manual solutions significantly.The improvements of production time and economic benefit compared with manual solutions are 10.5% and 7.3%,respectively. 展开更多
关键词 leaching process MODELING multi-objective optimization two-stage guide EXPERIMENT
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