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Parents' experience of caring for children with type 1 diabetes in China's Mainland: A qualitative study 被引量:2
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作者 Hui-Juan Tong Feng Qiu Ling Fan 《World Journal of Clinical Cases》 SCIE 2021年第11期2478-2486,共9页
BACKGROUND Parents of children with type 1 diabetes mellitus(T1DM)are under heavy caregiving stress,and parental caregivers'experience can affect the health outcomes of children with T1DM.AIM To describe the true ... BACKGROUND Parents of children with type 1 diabetes mellitus(T1DM)are under heavy caregiving stress,and parental caregivers'experience can affect the health outcomes of children with T1DM.AIM To describe the true inner feelings of parents caring for children with T1DM.METHODS Descriptive research methods were used to classify and summarize parents'experience when adapting to the role of caregivers for children with T1DM.The data was sorted and analyzed using content analysis.Themes of parents'experience caring for children with T1DM were refined,and their feelings were deeply investigated.RESULTS A total of 4 themes and 12 subthemes were identified:(1)Desire for information(disease-related information,home care information,and channels of information acquisition);(2)Skill guidance needs(insulin injection techniques,skills required for symptom management,and skills for parent-child communication);(3)Seeking emotional support(family support,peer support from other parents of children with T1DM,and professional support);and(4)Lack of social support(needs for financial support and needs for social security).Exploring the true experience of parents caring for children with T1DM is of great significance for helping them adapt to their role as caregivers.Nurses should provide professional guidance in terms of information,skills,emotion,and social support to parental caregivers. 展开更多
关键词 Type 1 diabetes CHILDREN parents Care experience Qualitative study Family management
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Exploring the Views of Parents of Children Following Telephone Advice from Nurses Working in a GP Out-of-Hours in Ireland
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作者 Abedallah Kasem 《Open Journal of Pediatrics》 2018年第4期334-346,共13页
This paper focuses on parents’ use and experiences of general practitioner (GP) out-of-hours (OOHs) services in Ireland. The progress in the establishment of GP OOHs services is considered by the Health Service Execu... This paper focuses on parents’ use and experiences of general practitioner (GP) out-of-hours (OOHs) services in Ireland. The progress in the establishment of GP OOHs services is considered by the Health Service Executive (HSE) to be a highly significant quality initiative for patient care, and the health service as a whole. Outside of normal GP surgery hours, parents of children can call a dedicated telephone number, to have their urgent health concerns assessed and to be advised about the appropriate level of care. Experienced nurses, who are often based in a GP OOHs centre, assess the call over the telephone and provide advice to the callers. The spur for conducting this study arose from my personal and professional experience which, I believe, underscores the need for exploring and understanding parents’ views of GP OOHs services, in order to bring about change in nurses’ practice of delivering advice over the telephone. The overall aim of the study is to explore and understand the views of parents of children, aged two years and under, following telephone advice received from nurses in the context of a GP out-of-hours service. A qualitative, exploratory, and descriptive design was used to examine the views and experiences of parents of children aged two years and under, who used a GP out-of-hours service provider in Ireland. Nine parents who had received phone advice from a nurse were purposively sampled to take part in the study. Data were collected using semi-structured interviews by telephone. Data were transcribed and analysed thematically. Themes included parents’ perceptions of illness in children with the need to be heard, parents’ views about accessibility to GP OOHs, parents’ expectations that the service would offer guidance and reassurance, parents’ satisfaction with the nurse’s advice, and parents’ experiences of hospital emergency departments (EDs). Suggestions for improving the GP OOHs service were made across these themes. The suggestions include: higher staffing levels, wanting a quicker call back, preference for face-to-face assessment over telephone advice and a preference for a children’s area in the GP OOHs. The study revealed that parents are satisfied with the GP OOHs service and the parental decision-making model has the potential to provide an opportunity to continue the progress of the establishment of GP OOHs services in Ireland. 展开更多
关键词 TELEPHONE ADVICE GP Out-of-Hours Patients’ experiences or VIEWS TELEPHONE Consultation parents VIEWS or experience parents of CHILDREN TELEPHONE Information Service Clinical Decision Support Software
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Psychosocial Experience of Parents of Children, Adolescents and Young Adults with Type 1 Diabetes in Brazzaville
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作者 Nestor Ghislain Andzouana Mbamognoua Rockiath Adou Osseni +4 位作者 Farel Elilie Mawa Ongoth Raissa Laure Mayanda Ohouna Evariste Bouenizabila Aymande Okoumou Moko Henri Germain Monabeka 《Health》 CAS 2022年第6期617-628,共12页
Type 1 diabetes is one of the main chronics pathologies in children. Efficient care requires a good knowledge of the disease by the parents, and an exploration of psychosocial experience of the parents, who are on the... Type 1 diabetes is one of the main chronics pathologies in children. Efficient care requires a good knowledge of the disease by the parents, and an exploration of psychosocial experience of the parents, who are on the front lines of the support. Objectives: Assess the impact of parents’ level of knowledge, from their psychosocial experience and from the quality of life on the glycemic control of children, adolescents and young adults with type 1 (DT1) diabetes in Brazzaville. Patients and Methods: This was an analytical cross-sectional study with prospective data collection during 7 months at Brazzaville University Hospital CHU, involving 103 parents. We studied socio-demographic variables, the balance of children’s diabetes by glycated hemoglobin, parents’ knowledge of diabetes by questionnaire “Michigan Diabetes Research and Training Center’s Revised Diabetes Knowledge Test”. The assessment of anxiety and depression through the “Hospital Anxiety and Depression” (HAD) score. Parental stress was assessed by the “Pediatric Inventory for Parents” (PIP). Results: We reported certain anxiety symptomatology in 60 parents (58.3%). Certain depression was reported in 63 parents (61.2%), and a lesser degree of parental distress. These psychosocial disorders in the parents did not influence the glycemic balance of the children. Low socio-economic level of the family (p = 0.001), poor knowledge about diabetes (p = 0.046) and poorer quality of life (p Conclusion: Psychosocial disorders were well observed in parents of DT1 children. 展开更多
关键词 KNOWLEDGE Quality of Life Psychosocial experience parents Type 1 Diabetes
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Permitted Visits to the ICU or Not—Children and Parents’ Experiences 被引量:1
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作者 Thi Huong Mai Thi Hoa Duong Anna-Lena Hellström 《Health》 CAS 2016年第11期1089-1097,共9页
Introduction: Children need intensive care in the first days after open-heart surgery. In some hospitals visits to Intensive Care Units (ICU), are not allowed, even by parents. Aim: The study aimed to illuminate the e... Introduction: Children need intensive care in the first days after open-heart surgery. In some hospitals visits to Intensive Care Units (ICU), are not allowed, even by parents. Aim: The study aimed to illuminate the experiences of children and parents regarding permission or not to visit the ICU. Subjects and Methods: Twenty children aged between 8 and 15 years with planned open-heart surgery, together with their parents, were chosen consecutively to participate in the study. They were divided into two groups. Group 1, followed the routine with no visits by parents allowed to the ICU. Group 2 were allowed such visits. Data were collected through open interviews with parents and children, following an interview guide. Results “Missing” was the overall theme illustrated in the findings, with two major categories;“being seen” and “taking care” being developed. The parents trusted the expert knowledge of the medical staff but Missing was strongly expressed and influenced the feelings within the categories in Group 1. Parents felt they were not seen and the lack of information made them anxious, frightened and feel they were losing control over their parenthood. They asked to see their children only briefly to allay their fears. They knew their children’s needs and thought they could help by taking care of practical issues to improve their well-being. All children in this group felt sad and abandoned. The families in Group 2 felt happy and confident despite not being allowed to stay with children all the time. The parents felt included in their care, which had a positive effect on the children. 展开更多
关键词 Parental Participation Visiting Hours for parents parents experiences
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Ultrafine tuning of the pore size in zeolite A for efficient propyne removal from propylene 被引量:1
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作者 Chaohui He Rajamani Krishna +3 位作者 Yang Chen Jiangfeng Yang Jinping Li Libo Li 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2021年第9期217-221,共5页
The removal of trace propyne(C_(3)H_(4))from propyne/propylene(C_(3)H_(4)/C_(3)H_(6))mixtures is a technical and challenging task during the production of polymer-grade propylene in view of their very similar size and... The removal of trace propyne(C_(3)H_(4))from propyne/propylene(C_(3)H_(4)/C_(3)H_(6))mixtures is a technical and challenging task during the production of polymer-grade propylene in view of their very similar size and physical properties.While some progress has been made,it is still very challenging to use some highly stable and commercially available porous materials via an energy-efficient adsorptive separation process.Herein,we report the ultrafine tuning of the pore apertures in type-A zeolites for the highly efficient removal of trace amounts of C_(3)H_(4)from C_(3)H_(4)/C_(3)H_(6)mixtures.The resulting ion-exchanged zeolite 5 A exhibits a large C_(3)H_(4)adsorption capacity(2.3 mmol g^(-1)under 10^(-4)MPa)and high C_(3)H_(4)/C_(3)H_(6)selectivity at room temperature,which were mainly attributed to the ultrafine-tuned pore size that selectively blocks C_(3)H_(6)molecules,while maintaining the stro ng adsorption of C_(3)H_(4)at low pressure region.High purity of C_(3)H_(6)(>99.9999%)can be directly obtained on this material under ambient conditions,as demonstrated by the experimental breakthrough curves obtained for both 1/99 and 0.1/99.9(V V)C_(3)H_(4)/C_(3)H_(6) mixtures. 展开更多
关键词 Type-A zeolite Ion-exchange Pore tuning Propyne/propylene separation Breakthrough experiments
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Extraction and Separation of Oxysophocarpine from Sophora alopecuroides by Reverse Three-phase Membrane Cycle Method 被引量:1
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作者 Kariyemu AIHAITI Mirzat MAIMAITI Arkin IBURAIM 《Medicinal Plant》 2017年第6期27-32,共6页
[Objectives] To establish the high performance liquid chromatography( HPLC) determination method for oxysophocarpine and optimize the extraction and purification technology of oxysophocarpine from Sophora alopecuroide... [Objectives] To establish the high performance liquid chromatography( HPLC) determination method for oxysophocarpine and optimize the extraction and purification technology of oxysophocarpine from Sophora alopecuroides by inverse three-phase membrane cycle.[Methods]Based on the single-factor experiment,the effects of aqueous phase and organic phase volume ratio,the concentration of sodium hydroxide,concentration of hydrochloric acid and extraction cycle time on extraction process of oxysophocarpine were investigated using orthogonal design method,to determine the optimal extraction process. [Results]The oxysophocarpine was determined by Shim-pack VP-ODS chromatographic column( 4. 6 mm × 250 mm,5 μm),mobile phase was methanol-0. 2% phosphoric acid aqueous solution( 7∶ 93),gradient elution,flow rate was 1 m L/min,the sample size was 5 μm,column temperature was 30℃,detection wavelength was 221 nm. Aqueous phase and organic phase volume ratio was 1∶ 1,hydrochloric acid concentration was 0. 3 mol/L,sodium hydroxide concentration was 0. 75 mol/L,water pump flow rate was 6 m L/min,60 min cycle time. The extraction rate of oxysophocarpine 98. 21 % within 60 min under the best experimental conditions. Oxysophocarpine has good linearity relationship within the range of 0. 01-0. 7 mg/m L( r^2= 0. 9978,n = 6),the respective average recovery rate was 97. 47%( RSD = 1. 95%). [Conclusions] This extraction process is simple in operation,the organic solvent has low consumption,and can be used for extraction of alkaloid. 展开更多
关键词 REVERSE phase MEMBRANE extraction and separation OXYSOPHOCARPINE PTFE MEMBRANE ULTRAVIOLET SPECTROPHOTOMETRY HPLC Orthogonal experiment
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Numerical Simulation and Experimental Investigation of 3 D Separated Flow Field around a Blunt Body
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作者 Doctoral Candidate: TAN Fa sheng Advisor: Prof. DAI Shi qiang Prof. WENG Pei fen (Shanghai Institute of Appllied Mathematics and Mechanics, Shanghai University) 《Advances in Manufacturing》 SCIE CAS 1999年第3期259-262,共4页
To study the effects of factors such as electromagnetic field and electron temperature on the ion extraction characteristics (extraction time, collision loss ratio) in atomic vapor laser isotope separation (AVLIS),... To study the effects of factors such as electromagnetic field and electron temperature on the ion extraction characteristics (extraction time, collision loss ratio) in atomic vapor laser isotope separation (AVLIS), 2 D electron equilibrium model was used to analyze and simulate the ion extraction process. The collisions between particles mainly considered charge exchanges between isotopic ions and atoms, which were treated by using cross section. The results show that the electric field and electron temperature have significant effects on the ion extraction characteristics: the stronger the electric field is, the higher the electron temperature is; the shorter the extraction time is, the less the collision loss ratio is, and moderate constant magnetic field has few effects on them. Key words atomic vapor laser isotope separation (AVLIS); ion extraction; charge exchange cross section; collision loss ratio 展开更多
关键词 blunt body separated flow numerical simulation NS equations flow visualization LDV experiment
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Treatment of Childhood Cancer in Southern Nigeria:Parents Perspective
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作者 Gracia Eke Nwadiuto Akani 《Psychology Research》 2019年第11期458-464,共7页
Background:The care and treatment of a child with cancer is stressful for parents.Recognizing their challenges and addressing them are important strategies in aiding families cope with cancer therapy.Objectives:To asc... Background:The care and treatment of a child with cancer is stressful for parents.Recognizing their challenges and addressing them are important strategies in aiding families cope with cancer therapy.Objectives:To ascertain the perspectives of parents on childhood cancer therapy and understand their challenges in order to devise effective ways of supporting them.Methods:This qualitative study was conducted between June and November 2018.Data were obtained through semi-structured interviews held with 27 parents whose children were being treated for various cancers at the Paediatric Oncology Unit of the University of Port Harcourt Teaching Hospital,Nigeria.Results:Respondents were 19 mothers,2 fathers,and 3 couples.Their children were aged 11 months to 15 years.Majority of respondent knew the diagnosis of their children while few could only name the site of the tumour.While undergoing chemotherapy,refusal to eat,vomiting,fever,pain,and falling of hairs were symptoms parents perceived as most distressing,which also affected them negatively.Treatment related costs drained families’monthly incomes and were considered the major challenge to treatment compliance.Financial support and prayers received were much appreciated and helped them cope better with their child’s therapy.Conclusion:Parents of children with cancer experience various stressors related to treatment.There is need to consistently offer them information regarding the side effects of cancer therapy and best ways of coping with them.They need to be supported in various ways to ensure compliance to their child’s therapy. 展开更多
关键词 experience parents TREATMENT of CHILDHOOD CANCER SOUTHERN NIGERIA
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Sex education for adolescents:Indonesian nurse educators’experience as parents
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作者 Alvin Salim Evelyn Hemme Tambunan 《Frontiers of Nursing》 2022年第3期303-310,共8页
Objectives:Sex education toward adolescent remains the most controversial subject due to the various thoughts and ideas of different values present in society.Nurse educators as parents must exemplify sex education to... Objectives:Sex education toward adolescent remains the most controversial subject due to the various thoughts and ideas of different values present in society.Nurse educators as parents must exemplify sex education to their children.The aim of this present study was to explore parents’experience,with nurse educators background to be exact,on how they convey sex education to their children.Methods:This study is a descriptive qualitative study,and the sample is recruited by using the purposive sampling technique.The qualified participants filled in the informed consent,provided demographic data,and were interviewed.Saturation data were obtained at the 6th interview in this study.The interview is transcribed to find themes and subthemes using conventional content analysis.Results:We derived 3 main themes:parents’approach,sex education topic,and children’s reaction.Parents’approach contained 4 subthemes,namely,gender match,parent-child closeness,media,and attitude.Sex education topic included 5 subthemes of bodily autonomy,health and safety,reproductive anatomy,puberty-related changes,and how to maintain healthiness.Children’s reaction experiences also included 4 subthemes of uncomfortable,questioning,acknowledging,and laughing.Conclusions:As a matter of fact,some parents in eastern countries,such as Indonesia,conveyed sex education to their children.Children might have various reactions to that topic,but it is important to keep them safe,especially in reproductive health,regardless of the culture or tradition.Based on nurse educators as exemplifiers,nurses and nursing students might acquire the picture in conveying sex education to adolescents. 展开更多
关键词 ADOLESCENT experiences Indonesian nurse educators parents and sex education
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Analysis and experimental study on resistance-increasing behavior of composite high efficiency autonomous inflow control device
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作者 Liang-Liang Dong Yu-Lin Zhang 《Petroleum Science》 SCIE EI CAS CSCD 2024年第2期1290-1304,共15页
Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks th... Bottom water coning is the main reason to reduce the recovery of horizontal bottom water reservoir. By water coning, we mean the oil-water interface changes from a horizontal state to a mound-shaped cone and breaks through to the wellbore. Autonomous inflow control device(AICD) is an important instrument maintain normal production after bottom water coning, however, the resistance increasing ability of the swirl type AICD is insufficient at present, which seriously affects the water control effect. Aiming this problem, this paper designs a multi-stage resistance-increasing and composite type AICD. The separation mechanism of oil-water two phases in this structure, the resistance form of oil-water single phase and the resistance-increasing principle of water phase are analyzed. Establishing the dual-phase multi-stage separation and resistance-increasing model, and verified by measuring the throttling pressure drop and oil-water volume fraction of the AICD, it is found that the composite type AICD has the effect of ICD and AICD at the same time, which can balance the production rate of each well section at the initial stage of production, delay the occurrence of bottom water coning. In the middle and later stages of production, water-blocking can be effectively increased to achieve water control and stable production.After structural sensitivity analysis, the influence law of various structural parameters on the water control performance of composite AICD was obtained. The simulation calculation results show that,compared with the existing swirl type AICD, composite AICD has higher sensitivity to moisture content,the water phase throttling pressure drop is increased by 4.5 times on average. The composite AICD is suitable for the entire stage of horizontal well production. 展开更多
关键词 Water control Flow separation Flow resistance-increasing AICD device Simulation and experiment
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Selective separation of Cu(Ⅱ),Zn(Ⅱ),and Cd(Ⅱ)by solvent extraction 被引量:12
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作者 XIE Keng WEN Jiankang +1 位作者 HUA Yixin RUAN Renman 《Rare Metals》 SCIE EI CAS CSCD 2008年第3期228-232,共5页
An experimental investigation was presented on the separation of Cu(Ⅱ), Zn(Ⅱ), and Cd(Ⅱ) from a rich sulfate leachate of zinc slag by solvent extraction. The results of orthogonal experiments indicate that LI... An experimental investigation was presented on the separation of Cu(Ⅱ), Zn(Ⅱ), and Cd(Ⅱ) from a rich sulfate leachate of zinc slag by solvent extraction. The results of orthogonal experiments indicate that LIX 984N is highly selective and very efficient in the extraction of Cu(Ⅱ), and the analysis of variance indicates that the sequence of parameters according to their influence on the separation efficiency is phase ratio 〉 LIX 984N concentration 〉 pH value 〉 extraction time. The optimal condition for copper extraction is obtained as 25% of LIX 984N concentration, 7 rain of extraction time, 3:2 of phase ratio O/A, and pH = 1.7. The separation of Zn(Ⅱ) and Cd(Ⅱ) was performed after the copper extraction from the raffinate. Comparative analysis of the separation with di-2-ethylhexyl phosphoric acid (D2EHPA), D2EHPA-tributyl- phosophate (TBP) synergistic extracting system, and 2-ethylhexyl phosphonic acid mono 2-ethylhexyl ester (HEHEHP) was made at pH = 2.0. It is demonstrated that the extraction efficiency with D2EHPA is improved after being saponified by sodium hydroxide, and D2EHPA-TBP synergistic extracting, as well as HEHEHP, has a superior selectivity to Zn(Ⅱ) over Cd(Ⅱ). 展开更多
关键词 solvent extraction selective separation copper(Ⅱ) zinc(Ⅱ) cadmium(Ⅱ) orthogonal experiment
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Experiment of Coal Leaching and Study of the Separation of Trace Elements 被引量:6
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作者 LIU Guijian 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2000年第2期386-390,共5页
Leaching is an important way of separation of trace elements from coal. Based on leaching experiments, the content of trace elements separated out from coal is related to their existing state and content in coal, the ... Leaching is an important way of separation of trace elements from coal. Based on leaching experiments, the content of trace elements separated out from coal is related to their existing state and content in coal, the duration of leaching process, temperature of leaching liquor and its acidity and basicity. The higher the temperature of leaching liquor and the longer the leaching time, the higher the contents of separated trace elements will be. In the course of leaching, the pH values of leaching liquors change and different trace elements are affected differently by the pH values. 展开更多
关键词 Leaching experiment trace elements influence factors separation of trace element
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Numerical simulation and optimization of red mud separation thickener with self-dilute feed 被引量:4
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作者 周天 李茂 +1 位作者 周谦 周孑民 《Journal of Central South University》 SCIE EI CAS 2014年第1期344-350,共7页
In order to acquire the flow pattern and investigate the settling behavior of the red mud in the separation thickener,computational fluid dynamics(CFD),custom subroutines and agglomerates settling theory were employed... In order to acquire the flow pattern and investigate the settling behavior of the red mud in the separation thickener,computational fluid dynamics(CFD),custom subroutines and agglomerates settling theory were employed to simulate the three-dimensional flow field in an industrial scale thickener with the introduction of a self-dilute feed system.The simulation results show good agreement with the measurement onsite and the flow patterns of the thickener are presented and discussed on both velocity and concentration field.Optimization experiments on feed well and self-dilute system were also carried out,and indicate that the optimal thickener system can dilute the solid concentration in feed well from 110 g/L to 86 g/L which would help the agglomerates' formation and improve the red mud settling speed.Furthermore,the additional power of recirculation pump can be saved and flocculants dosage was reduced from 105g/t to 85g/t in the operation. 展开更多
关键词 separation thickener self-dilute feed system numerical simulation optimization experiments computational fluiddynamics
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Impacts of soil properties on phosphorus adsorption and fractions in purple soils 被引量:1
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作者 XIAO Yi TANG Jia-liang +2 位作者 WANG Ming-kuang ZHAI Long-bo ZHANG Xi-feng 《Journal of Mountain Science》 SCIE CSCD 2017年第12期2420-2431,共12页
Information on phosphorus(P) adsorption and its impacts on the redistribution of the P fraction in soil profiles are important for environmental management under intensive agricultural practices.To clarify the dominan... Information on phosphorus(P) adsorption and its impacts on the redistribution of the P fraction in soil profiles are important for environmental management under intensive agricultural practices.To clarify the dominant factors influencing soil phosphorus adsorption in an Entisol(locally known as purple soil), P adsorption experiments were conducted in Sichuan Basin of southwestern China for cropland and woodland soils with acidic, neutral and calcareous origins throughout their profile. After various doses of P were added during incubation experiments, soil P fractions were also analyzed. The results showed that there were no significant differences in Fe-oxides and P adsorption along the vertical gradients. Agricultural practices and lower p H conditions reduced the P adsorption capacity of purple soils throughout the soil profiles. For acidic and neutral purple soil profiles, the P adsorption capability was mainly influenced by Fe-oxides and soil texture. Ca-bound P and Fe-Al-bound P represented the majority of the total inorganic P of calcareous soils.There was a saturation of adsorption capacity by sesquioxide and a high risk of dissoluble reactive P(NH_4 Cl-P) being released out of the soil profile in acidic and neutral purple soils after the greatest P addition, indicated by the higher proportions of NH_4 Cl-P(over 40%) and decreasing Fe-Al-P fraction.P fractions migrated with greater difficulty in calcareous purple soil profiles as Ca-P fraction peaked over 65% when adding a P dose at or greater than 80 g P kg^(-1), indicating the high potential of P adsorption.The X-Ray Diffraction analysis also verified the formation of brushite. Adaptive management practices should be designed to alleviate P losses for acidic and neutral purple soils. 展开更多
关键词 AGROECOLOGY Soil parent material Feoxides Phosphorus adsorption Incubation experiment Phosphorus fraction
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Effects of Bulbous Bow on Cross-Flow Vortex Structures Around a Streamlined Submersible Body at Intermediate Pitch Maneuver: A Numerical Investigation 被引量:1
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作者 Saeed Abedi Ali Akbar Dehghan +1 位作者 Ali Saeidinezhad Mojtaba Dehghan Manshadi 《Journal of Marine Science and Application》 CSCD 2016年第1期8-15,共8页
A flow field around a streamlined body at an intermediate angle of incidence is dominated by cross-flow separation and vortical flow fields. The separated flow leads to a pair of vortices on the leeside of the body; t... A flow field around a streamlined body at an intermediate angle of incidence is dominated by cross-flow separation and vortical flow fields. The separated flow leads to a pair of vortices on the leeside of the body; therefore, it is essential to accurately determine this pair and estimate its size and location. This study utilizes the element-based finite volume method based on RANS equations to compute a 3D axisymmetric flow around a SUBOFF bare submarined hull. Cross-flow vortex structures are then numerically simulated and compared for a submarine with SUBOFF and DRDC STR bows. Computed results of pressure and shear stress distribution on the hull surface and the strength and locations of the vortex structures are presented at an intermediate incidence angle of 20°. A wind tunnel experiment is also conducted to experimentally visualize the vortex structures and measure their core locations. These experimental results are compared with the numerical data, and a good agreement is found. 展开更多
关键词 SUBMARINE intermediate angle cross-flow separation vortex structures computational fluid dynamics (CFD) wind tunnel experiment
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Water storage changes in North America retrieved from GRACE gravity and GPS data 被引量:2
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作者 Wang Hansheng Xiang Longwei +4 位作者 Jia Lulu Wu Patrick Steffen Holger Jiang Liming Shen Qiang 《Geodesy and Geodynamics》 2015年第4期267-273,共7页
As global warming continues,the monitoring of changes in terrestrial water storage becomes increasingly important since it plays a critical role in understanding global change and water resource management.In North Am... As global warming continues,the monitoring of changes in terrestrial water storage becomes increasingly important since it plays a critical role in understanding global change and water resource management.In North America as elsewhere in the world,changes in water resources strongly impact agriculture and animal husbandry.From a combination of Gravity Recovery and Climate Experiment(GRACE) gravity and Global Positioning System(GPS) data,it is recently found that water storage from August,2002 to March,2011 recovered after the extreme Canadian Prairies drought between 1999 and 2005.In this paper,we use GRACE monthly gravity data of Release 5 to track the water storage change from August,2002 to June,2014.In Canadian Prairies and the Great Lakes areas,the total water storage is found to have increased during the last decade by a rate of 73.8 ± 14.5 Gt/a,which is larger than that found in the previous study due to the longer time span of GRACE observations used and the reduction of the leakage error.We also find a long term decrease of water storage at a rate of-12.0 ± 4.2 Gt/a in Ungava Peninsula,possibly due to permafrost degradation and less snow accumulation during the winter in the region.In addition,the effect of total mass gain in the surveyed area,on present-day sea level,amounts to-0.18 mm/a,and thus should be taken into account in studies of global sea level change. 展开更多
关键词 Canadian Prairies Great Lakes Ungava Peninsula Water storage changes Gravity Recovery and Climate Experiment (GRACE) data Global Positioning System (GPS) data Glacial isostatic adjustment Separation approach
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双金属MOFs的NO/CO_(2)选择性吸附性能研究
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作者 李磊 胡洁 +3 位作者 李豪 翟颖 张哲 唐富顺 《化工新型材料》 CAS CSCD 北大核心 2023年第9期225-230,共6页
采用溶剂热法合成制备含Co、Mn双金属节点的MOF-74材料,研究了室温下对NO的吸附性能,并通过IAST和穿透实验研究了材料的吸附选择性。结果表明,双金属Mn_(0.2)Co_(0.8)-MOF-74具有典型的MOF-74晶体结构,对NO的吸附量达到160.3cc/g,比单金... 采用溶剂热法合成制备含Co、Mn双金属节点的MOF-74材料,研究了室温下对NO的吸附性能,并通过IAST和穿透实验研究了材料的吸附选择性。结果表明,双金属Mn_(0.2)Co_(0.8)-MOF-74具有典型的MOF-74晶体结构,对NO的吸附量达到160.3cc/g,比单金属Mn-MOF-74提高了约19.4%。在低吸附分压时,NO/CO_(2)的理想溶液吸附(IAST)理论吸附选择性最大可达到397,经过5次循环吸附-脱附实验后的再生性能优良。模拟烟气的双组分穿透实验中,Mn_(0.2)Co_(0.8)-MOF-74对NO/CO_(2)的吸附分离性能达到35.5,可以作为一种优良的NO吸附分离材料。 展开更多
关键词 双金属有机骨架材料 NO/CO_(2)吸附分离 吸附选择性 穿透实验
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Manipulation of vertical fence wake using passive vortex generators
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作者 Kim Hyoung-Bum Kim Seoung-Jun +4 位作者 Tu Xin-Cheng Park Seung-Ha Kim Seoung-Jun Tu Xin-Cheng Park Seung-Ha 《排灌机械工程学报》 EI 北大核心 2014年第5期369-372,377,共5页
The effect of streamwise vortices generated from passive vortex generators was investigated to manipulate the separation bubble behind the vertical fence. The experiments were carried out in a circulating water channe... The effect of streamwise vortices generated from passive vortex generators was investigated to manipulate the separation bubble behind the vertical fence. The experiments were carried out in a circulating water channel and the velocity fields were measured using 2D and stereoscopic PIV method.The distance between the vortex generator and fence and the effect of the Reynolds number were investigated. In addition,the effect of boundary layer thickness was also investigated. The averaged recirculation lengths were compared with that of uncontrolled fence flow. The results showed the oscillatory variation of recirculation region appeared under the existence of vortex generators. The reduction of the separation bubble became larger when the fence was submerged in the thick boundary layer with increasing the distance between the generator and fence. When the boundary layer is thin,vortex generator can only suppress the separation bubble under the specific condition. 展开更多
关键词 vortex generator flow separation stereoscopic PIV EXPERIMENT
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Kolmogorov’s Probability Spaces for “Entangled” Data-Subsets of EPRB Experiments: No Violation of Einstein’s Separation Principle 被引量:1
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作者 Karl Hess 《Journal of Modern Physics》 2020年第5期683-702,共20页
It is demonstrated that the use of Kolmogorov’s probability theory to describe results of quantum probability for EPRB (Einstein-Podolsky-Rosen-Bohm) experiments requires extreme care when different subsets of measur... It is demonstrated that the use of Kolmogorov’s probability theory to describe results of quantum probability for EPRB (Einstein-Podolsky-Rosen-Bohm) experiments requires extreme care when different subsets of measurement outcomes are considered. J. S. Bell and his followers have committed critical inaccuracies related to spin-gauge and probability measures of such subsets, because they use exclusively a single probability space for all data sets and sub-sets of data. It is also shown that Bell and followers use far too stringent epistemological requirements for the consequences of space-like separation. Their requirements reach way beyond Einstein’s separation principle and cannot be met by the major existing physical theories including relativity and even classical mechanics. For example, the independent free will does not empower the experimenters to choose multiple independent spin-gauges in the two EPRB wings. It is demonstrated that the suggestion of instantaneous influences at a distance (supposedly “derived” from experiments with entangled quantum entities) is a consequence of said inaccuracies and takes back rank as soon as the Kolmogorov probability measures are related to a consistent global spin-gauge and permitted to be different for different data subsets: Using statistical interpretations and different probability spaces for certain subsets of outcomes instead of probability amplitudes related to single quantum entities, permits physical explanations without a violation of Einstein’s separation principle. 展开更多
关键词 Bell’s Theorem Einstein’s Separation Principle EPRB Experiments
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Categories of Nonlocality in EPR Theories and the Validity of Einstein’s Separation Principle as Well as Bell’s Theorem
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作者 Karl Hess 《Journal of Modern Physics》 2019年第10期1209-1221,共13页
Work on quantum entanglement is currently emphasizing the nonlocal nature of theories that attempt to explain spatially separated Einstein-Podolsky-Rosen (EPR) correlation experiments. It is frequently claimed that no... Work on quantum entanglement is currently emphasizing the nonlocal nature of theories that attempt to explain spatially separated Einstein-Podolsky-Rosen (EPR) correlation experiments. It is frequently claimed that nonlocal instantaneous influences, or equivalently a breakdown of Einstein’s separation principle, are a signature property of (quantum) entanglement. This paper presents a categorization of the various forms of nonlocality in physical theories. It is shown that, even for Einstein’s theory of relativity, correlations of spatially separated measurements cannot be explained without the involvement of some nonlocal or global knowledge and facts. Instantaneous Influences at a distance are, however, in a special category of nonlocality and, as is well known, Einstein called them spooky. Following a separation of nonlocalities into four distinctly different categories 0, 1, 2, 3, with number 3 corresponding to theories containing instantaneous influences at a distance, I show that any theory of EPR experiments must be at least in category 1 or 2 and does not need to be in category 3. In particular, the Bell theorem, valid for category 0 theories, may be violated for categories 1 and 2 and does not require category 3 theories. Category 0 enforces Bell’s theorem. However, it does not apply to relativistic theories of space like separated measurements. 展开更多
关键词 Bell’s THEOREM Einstein’s Separation PRINCIPLE EPRB Experiments
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