期刊文献+
共找到231,619篇文章
< 1 2 250 >
每页显示 20 50 100
Catalyst–Support Interaction in Polyaniline‑Supported Ni_(3)Fe Oxide to Boost Oxygen Evolution Activities for Rechargeable Zn‑Air Batteries
1
作者 Xiaohong Zou Qian Lu +8 位作者 Mingcong Tang Jie Wu Kouer Zhang Wenzhi Li Yunxia Hu Xiaomin Xu Xiao Zhang Zongping Shao Liang An 《Nano-Micro Letters》 SCIE EI CAS 2025年第1期176-190,共15页
Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3... Catalyst–support interaction plays a crucial role in improving the catalytic activity of oxygen evolution reaction(OER).Here we modulate the catalyst–support interaction in polyaniline-supported Ni_(3)Fe oxide(Ni_(3)Fe oxide/PANI)with a robust hetero-interface,which significantly improves oxygen evolution activities with an overpotential of 270 mV at 10 mA cm^(-2)and specific activity of 2.08 mA cm_(ECSA)^(-2)at overpotential of 300 mV,3.84-fold that of Ni_(3)Fe oxide.It is revealed that the catalyst–support interaction between Ni_(3)Fe oxide and PANI support enhances the Ni–O covalency via the interfacial Ni–N bond,thus promoting the charge and mass transfer on Ni_(3)Fe oxide.Considering the excellent activity and stability,rechargeable Zn-air batteries with optimum Ni_(3)Fe oxide/PANI are assembled,delivering a low charge voltage of 1.95 V to cycle for 400 h at 10 mA cm^(-2).The regulation of the effect of catalyst–support interaction on catalytic activity provides new possibilities for the future design of highly efficient OER catalysts. 展开更多
关键词 Catalyst-support interaction supported catalysts HETEROINTERFACE Oxygen evolution reaction Zn-air batteries
下载PDF
Fuzzy-support vector machine geotechnical risk analysis method based on Bayesian network 被引量:5
2
作者 LIU Yang ZHANG Jian-jing +2 位作者 ZHU Chong-hao XIANG Bo WANG Dong 《Journal of Mountain Science》 SCIE CSCD 2019年第8期1975-1985,共11页
Machine learning method has been widely used in various geotechnical engineering risk analysis in recent years. However, the overfitting problem often occurs due to the small number of samples obtained in history. Thi... Machine learning method has been widely used in various geotechnical engineering risk analysis in recent years. However, the overfitting problem often occurs due to the small number of samples obtained in history. This paper proposes the FuzzySVM(support vector machine) geotechnical engineering risk analysis method based on the Bayesian network. The proposed method utilizes the fuzzy set theory to build a Bayesian network to reflect prior knowledge, and utilizes the SVM to build a Bayesian network to reflect historical samples. Then a Bayesian network for evaluation is built in Bayesian estimation method by combining prior knowledge with historical samples. Taking seismic damage evaluation of slopes as an example, the steps of the method are stated in detail. The proposed method is used to evaluate the seismic damage of 96 slopes along roads in the area affected by the Wenchuan earthquake. The evaluation results show that the method can solve the overfitting problem, which often occurs if the machine learning methods are used to evaluate risk of geotechnical engineering, and the performance of the method is much better than that of the previous machine learning methods. Moreover,the proposed method can also effectively evaluate various geotechnical engineering risks in the absence of some influencing factors. 展开更多
关键词 GEOtechnical evaluation OVERFITTING problem BAYESIAN network Prior knowledge FUZZY set theory support vector machine
下载PDF
Probabilistic back analysis for geotechnical engineering based on Bayesian and support vector machine 被引量:2
3
作者 陈炳瑞 赵洪波 +1 位作者 茹忠亮 李贤 《Journal of Central South University》 SCIE EI CAS CSCD 2015年第12期4778-4786,共9页
Geomechanical parameters are complex and uncertain.In order to take this complexity and uncertainty into account,a probabilistic back-analysis method combining the Bayesian probability with the least squares support v... Geomechanical parameters are complex and uncertain.In order to take this complexity and uncertainty into account,a probabilistic back-analysis method combining the Bayesian probability with the least squares support vector machine(LS-SVM) technique was proposed.The Bayesian probability was used to deal with the uncertainties in the geomechanical parameters,and an LS-SVM was utilized to establish the relationship between the displacement and the geomechanical parameters.The proposed approach was applied to the geomechanical parameter identification in a slope stability case study which was related to the permanent ship lock within the Three Gorges project in China.The results indicate that the proposed method presents the uncertainties in the geomechanical parameters reasonably well,and also improves the understanding that the monitored information is important in real projects. 展开更多
关键词 geotechnical engineering back analysis UNCERTAINTY Bayesian theory least square method support vector machine(SVM)
下载PDF
A web site for online training,technical support and scientific information for nucleic acidt esting:www.ebloodbank.com
4
《中国输血杂志》 CAS CSCD 2001年第S1期402-,共1页
关键词 WWW A web site for online training technical support and scientific information for nucleic acidt esting
下载PDF
Classification and technical target of water electrolysis for hydrogen production 被引量:2
5
作者 Kahyun Ham Sooan Bae Jaeyoung Lee 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第8期554-576,I0012,共24页
Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate change.Water electrolysis technology,in conjunction with renewable energy,is considered the most feasible hydrogen pro... Continuous efforts are underway to reduce carbon emissions worldwide in response to global climate change.Water electrolysis technology,in conjunction with renewable energy,is considered the most feasible hydrogen production technology based on the viable possibility of large-scale hydrogen production and the zero-carbon-emission nature of the process.However,for hydrogen produced via water electrolysis systems to be utilized in various fields in practice,the unit cost of hydrogen production must be reduced to$1/kg H_(2).To achieve this unit cost,technical targets for water electrolysis have been suggested regarding components in the system.In this paper,the types of water electrolysis systems and the limitations of water electrolysis system components are explained.We suggest guideline with recent trend for achieving this technical target and insights for the potential utilization of water electrolysis technology. 展开更多
关键词 Water electrolysis Hydrogen production technical target ELECTROCHEMISTRY
下载PDF
Dysfunctional attitudes,social support,negative life events,and depressive symptoms in Chinese adolescents:A moderated mediation model 被引量:2
6
作者 Teng-Fei Yu Li Liu +3 位作者 Lu-Ning Shang Fang-Fang Xu Zhi-Min Chen Li-Ju Qian 《World Journal of Psychiatry》 SCIE 2024年第11期1671-1680,共10页
BACKGROUND Depression is a prevalent psychological issue in adolescents that is significantly related to negative life events(NLEs)and dysfunctional attitudes.High levels of social support can significantly buffer NLE... BACKGROUND Depression is a prevalent psychological issue in adolescents that is significantly related to negative life events(NLEs)and dysfunctional attitudes.High levels of social support can significantly buffer NLEs’effect on depression.Currently,there is limited research on how social support moderates the relationship between NLEs,dysfunctional attitudes,and depression in adolescents in China.It is imperative to investigate this moderating effect to mitigate dysfunctional attitudes in adolescent undergoing depressive mood,ultimately enhancing their overall mental health.AIM To investigate the relationship and underlying mechanisms between specific dysfunctional attitudes,social support,and depression among Chinese adolescents.METHODS This is a cross-sectional study which selected five middle schools in Shandong Province for investigation in March 2022.Participants included 795 adolescents(49.87%male,mage=15.15,SD=1.84,age range=11-18 years old).All participants completed the Dysfunctional Attitude Scale,Adolescent Life Event Scale,Beck Depression Inventory,and Social Support Rating Scale.A moderated mediation model was conducted to examine the relationship between specific dysfunctional attitudes,social support,and depression.RESULTS Results indicated that NLEs affected depression through the mediating role of specific dysfunctional attitudes(autonomy attitudesβ=0.21;perfectionismβ=0.25).Moreover,social support was found to moderate the mediating effect between NLEs,specific dysfunctional attitudes,and depressive symptoms(autonomy attitudes b2=-0.08;perfectionism b2=-0.09).CONCLUSION Dysfunctional attitudes mediated and social support moderated the relationship between NLEs and depression.Social support can buffer depression symptoms among adolescents with autonomy attitudes and perfectionism. 展开更多
关键词 DEPRESSION Dysfunctional attitudes Social support Adolescents Moderated mediation model
下载PDF
Mechanism of high-preload support based on the NPR anchor cable in layered soft rock tunnels 被引量:1
7
作者 SUI Qiru HE Manchao +3 位作者 SHI Mengfan TAO Zhigang ZHAO Feifei ZHANG Xiaoyu 《Journal of Mountain Science》 SCIE CSCD 2024年第4期1403-1418,共16页
The control of large deformation problems in layered soft rock tunnels needs to solve urgently.The roof problem is particularly severe among the deformation issues in tunnels.This study first analyzes the asymmetric d... The control of large deformation problems in layered soft rock tunnels needs to solve urgently.The roof problem is particularly severe among the deformation issues in tunnels.This study first analyzes the asymmetric deformation modes in layered soft rock tunnels with large deformations.Subsequently,we construct a mechanical model under ideal conditions for controlling the roof of layered soft rock tunnels through high preload with the support of NPR anchor cables.The prominent roles of long and short NPR anchor cables in the support system are also analyzed.The results indicate the significance of high preload in controlling the roof of layered soft rock tunnels.The short NPR anchor cables effectively improve the integrity of the stratified soft rock layers,while the long NPR anchor cables effectively mobilize the self-bearing capacity of deep-stable rock layers.Finally,the high-preload support method with NPR anchor cables is validated to have a good effect on controlling large deformations in layered soft rock tunnels through field monitoring data. 展开更多
关键词 Tunnel engineering Soft rock High-preload support NPR anchor cables
下载PDF
Analysis of the interaction between bolt-reinforced rock and surface support in tunnels based on convergence-confinement method 被引量:2
8
作者 Zhenyu Sun Dingli Zhang +2 位作者 Qian Fang Yanjuan Hou Nanqi Huangfu 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期1936-1951,共16页
To investigate the interaction of the bolt-reinforced rock and the surface support,an analytical model of the convergence-confinement type is proposed,considering the sequential installation of the fully grouted rockb... To investigate the interaction of the bolt-reinforced rock and the surface support,an analytical model of the convergence-confinement type is proposed,considering the sequential installation of the fully grouted rockbolts and the surface support.The rock mass is assumed to be elastic-brittle-plastic material,obeying the linear Mohr-Coulomb criterion or the non-linear Hoek-Brown criterion.According to the strain states of the tunnel wall at bolt and surface support installation and the relative magnitude between the bolt length and the plastic depth during the whole process,six cases are categorized upon solving the problem.Each case is divided into three stages due to the different effects of the active rockbolts and the passive surface support.The fictitious pressure is introduced to quantify the threedimensional(3D)effect of the tunnel face,and thus,the actual physical location along the tunnel axis of the analytical section can be considered.By using the bolt-rock strain compatibility and the rocksurface support displacement compatibility conditions,the solutions of longitudinal tunnel displacement and the reaction pressure of surface support along the tunnel axis are obtained.The proposed analytical solutions are validated by a series of 3D numerical simulations.Extensive parametric studies are conducted to examine the effect of the typical parameters of rockbolts and surface support on the tunnel displacement and the reaction pressure of the surface support under different rock conditions.The results show that the rockbolts are more effective in controlling the tunnel displacement than the surface support,which should be installed as soon as possible with a suitable length.For tunnels excavated in weak rocks or with restricted displacement control requirements,the surface support should also be installed or closed timely with a certain stiffness.The proposed method provides a convenient alternative approach for the optimization of rockbolts and surface support at the preliminary stage of tunnel design. 展开更多
关键词 Analytical model Longitudinal tunnel displacement Fictitious pressure Active rockbolts Surface support reaction pressure Tunnel design
下载PDF
Experimental Geotechnical Characterization Campaign of the Matam Soil for Lithology: Application to the Study of Supports of the Balterdi Bridge
9
作者 Abdoulaye Diedhiou Libasse Sow +2 位作者 Gorgui Thierno Yoro Diouf Mbene Diop Ndeye Mareme Diop 《Open Journal of Civil Engineering》 2021年第2期200-215,共16页
This paper presents a geotechnical study whose objective is to determine the lithology of the soil of Balterdi village (Matam, Senegal). A bridge-type structure with six supports is to be built on the studied site. Th... This paper presents a geotechnical study whose objective is to determine the lithology of the soil of Balterdi village (Matam, Senegal). A bridge-type structure with six supports is to be built on the studied site. The drilling program consisted of six core drillings (SC) each 30 m deep with sampling and six destructive drillings with pressuremeter tests (SP) every 1.5 m up to 30 m deep. A pair of core and pressuremeter tests was carried out under each support. From the results of the core drill holes and the geological model of the site, it can be seen that the lithology of the soil along the structure consists essentially of soft clay layers, becoming firm at depth over the first 18 m on average (with some incursions of sandy layers) resting on medium to compacted sand up to 30 m. Brown clayey fill is also present between piers P3 and P5. The presence of a watercourse along the structure is noted. The foundations will therefore be carried out in the water. The results of the pressuremeter tests confirm the homogeneity of the soil over the whole area. Indeed, the values obtained are almost similar for all the tests. According to the limit pressures obtained, the clayey-sandy formations encountered along the structure are respectively soft to firm and moderately compact to compact. Their limit pressures are high enough to allow good bearing capacities. 展开更多
关键词 Geotechnical Behaviour Cored Surveys Pressuremeter Surveys LITHOLOGY Bridge supports
下载PDF
Stability analysis of longwall top-coal caving face in extra-thick coal seams based on an innovative numerical hydraulic support model 被引量:1
10
作者 Jun Guo Wenbo Huang +7 位作者 Guorui Feng Jinwen Bai Lirong Li Zi Wang Luyang Yu Xiaoze Wen Jie Zhang Wenming Feng 《International Journal of Mining Science and Technology》 SCIE EI CAS CSCD 2024年第4期491-505,共15页
The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining process.In view of the fact that most of the existing numerical simulation methods construct ... The relationship between support and surrounding rock is of great significance to the control of surrounding rock in mining process.In view of the fact that most of the existing numerical simulation methods construct virtual elements and stress servo control to approximately replace the hydraulic support problem,this paper establishes a new numerical model of hydraulic support with the same working characteristics as the actual hydraulic support by integrating numerical simulation software Rhino,Griddle and FLAC3D,which can realize the simulation of different working conditions.Based on this model,the influence mechanism of the supporting strength of hydraulic support on surrounding rock stress regulation and coal stability in front of the top coal caving face in extra thick coal seam were researched.Firstly,under different support intensity,the abutment pressure of the bearing coal and the coal in front of it presents the “three-stage”evolution characteristics.The influence range of support intensity is 15%–30%.Secondly,1.5 MPa is the upper limit of impact that the support strength can have on the front coal failure area.Thirdly,within a displacement range of 2.76 m from the coal wall,a support strength of1.5 MPa provides optimal control of the horizontal displacement of the coal. 展开更多
关键词 Extremely thick coal seam Fully mechanized top coal caving support strength support-surrounding rock interaction
下载PDF
Translocation of telomerase reverse transcriptase coincided with ATP release in postnatal cochlear supporting cells 被引量:1
11
作者 Yukai Zhang Keyong Tian +9 位作者 Wei Wei Wenjuan Mi Fei Lu Zhenzhen Liu Qingwen Zhu Xinyu Zhang Panling Geng Jianhua Qiu Yongli Song Dingjun Zha 《Neural Regeneration Research》 SCIE CAS CSCD 2024年第5期1119-1125,共7页
The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechani... The spontaneous bursts of electrical activity in the developing auditory system are derived from the periodic release of adenosine triphosphate(ATP)by supporting cells in the Kölliker’s organ.However,the mechanisms responsible for initiating spontaneous ATP release have not been determined.Our previous study revealed that telomerase reverse transcriptase(TERT)is expressed in the basilar membrane during the first postnatal week.Its role in cochlear development remains unclear.In this study,we investigated the expression and role of TERT in postnatal cochlea supporting cells.Our results revealed that in postnatal cochlear Kölliker’s organ supporting cells,TERT shifts from the nucleus into the cytoplasm over time.We found that the TERT translocation tendency in postnatal cochlear supporting cells in vitro coincided with that observed in vivo.Further analysis showed that TERT in the cytoplasm was mainly located in mitochondria in the absence of oxidative stress or apoptosis,suggesting that TERT in mitochondria plays roles other than antioxidant or anti-apoptotic functions.We observed increased ATP synthesis,release and activation of purine signaling systems in supporting cells during the first 10 postnatal days.The phenomenon that TERT translocation coincided with changes in ATP synthesis,release and activation of the purine signaling system in postnatal cochlear supporting cells suggested that TERT may be involved in regulating ATP release and activation of the purine signaling system.Our study provides a new research direction for exploring the spontaneous electrical activity of the cochlea during the early postnatal period. 展开更多
关键词 apoptosis ATP release Ca2+transients COCHLEA mitochondrial function reactive oxygen species spontaneous electrical activity supporting cells
下载PDF
The Effection Analysis of Geotechnical Investigation on Foundation Pit Supporting Construction
12
作者 Weiwei Xu 《Frontiers Research of Architecture and Engineering》 2021年第1期26-31,共6页
With the continuous development of the construction industry,the density of engineering construction and the difficulty of underground construction are also increasing.As an important construction protection measure,f... With the continuous development of the construction industry,the density of engineering construction and the difficulty of underground construction are also increasing.As an important construction protection measure,foundation pit support construction is widely used in underground construction.Starting from the characteristics of foundation pit support construction,this paper analyzes the influence of geotechnical investigation on foundation pit support construction,and analyzes the problems that need to be paid attention to in the survey process. 展开更多
关键词 Geotechnical investigation Foundation pit support Construction effect
下载PDF
Construction of a nomogram model to predict technical difficulty in performing laparoscopic sphincter-preserving radical resection for rectal cancer
13
作者 Xiao-Cong Zhou Shi-Wei Guan +3 位作者 Fei-Yue Ke Gaurav Dhamija Qiang Wang Bang-Fei Chen 《World Journal of Gastroenterology》 SCIE CAS 2024年第18期2418-2439,共22页
BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic cavities.Therefore,it is essential for colorectal surgeons... BACKGROUND Colorectal surgeons are well aware that performing surgery for rectal cancer becomes more challenging in obese patients with narrow and deep pelvic cavities.Therefore,it is essential for colorectal surgeons to have a comprehensive understanding of pelvic structure prior to surgery and anticipate potential surgical difficulties.AIM To evaluate predictive parameters for technical challenges encountered during laparoscopic radical sphincter-preserving surgery for rectal cancer.METHODS We retrospectively gathered data from 162 consecutive patients who underwent laparoscopic radical sphincterpreserving surgery for rectal cancer.Three-dimensional reconstruction of pelvic bone and soft tissue parameters was conducted using computed tomography(CT)scans.Operative difficulty was categorized as either high or low,and multivariate logistic regression analysis was employed to identify predictors of operative difficulty,ultimately creating a nomogram.RESULTS Out of 162 patients,21(13.0%)were classified in the high surgical difficulty group,while 141(87.0%)were in the low surgical difficulty group.Multivariate logistic regression analysis showed that the surgical approach using laparoscopic intersphincteric dissection,intraoperative preventive ostomy,and the sacrococcygeal distance were independent risk factors for highly difficult laparoscopic radical sphincter-sparing surgery for rectal cancer(P<0.05).Conversely,the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance was identified as a protective factor(P<0.05).A nomogram was subsequently constructed,demonstrating good predictive accuracy(C-index=0.834).CONCLUSION The surgical approach,intraoperative preventive ostomy,the sacrococcygeal distance,and the anterior-posterior diameter of pelvic inlet/sacrococcygeal distance could help to predict the difficulty of laparoscopic radical sphincter-preserving surgery. 展开更多
关键词 NOMOGRAM Rectal cancer Laparoscopic operation Sphincter-preserving surgery technical difficulty
下载PDF
Roles of supporting cells in the maintenance and regeneration of the damaged inner ear:A literature review
14
作者 Jing-Ying Guo Jun-Yi Xu +1 位作者 Shu-Sheng Gong Guo-Peng Wang 《Journal of Otology》 CAS CSCD 2024年第4期234-240,共7页
The inner ear sensory epithelium consists of two major types of cells:hair cells(HCs)and supporting cells(SCs).Critical functions of HCs in the perception of mechanical stimulation and mechanosensory transduction have... The inner ear sensory epithelium consists of two major types of cells:hair cells(HCs)and supporting cells(SCs).Critical functions of HCs in the perception of mechanical stimulation and mechanosensory transduction have long been elucidated.SCs are indispensable components of the sensory epithelia,and they maintain the structural integrity and ionic environment of the inner ear.Once delicate inner ear epithelia sustain injuries(for example,due to ototoxic drugs or noise exposure),SCs respond immediately to serve as repairers of the epithelium and as adapters to become HC progenitors,aiming at morphological and functional recovery of the inner ear.This regenerative process is extensive in non-mammals,but is limited in the mammalian inner ear,especially in the mature cochlea.This review aimed to discuss the important roles of SCs in the repair of the mammalian inner ear. 展开更多
关键词 EPITHELIUM INJURIES supportING
下载PDF
Research on the origin and evolution of technical management regulations for railway
15
作者 Lei Tian Yuming Sun Yonggang Jia 《Railway Sciences》 2024年第6期779-787,共9页
Purpose–To facilitate technical managers and field workers to master and understand the provisions of Technical Management Regulations for Railway more accurately,so as to better serve the comprehensive revision of t... Purpose–To facilitate technical managers and field workers to master and understand the provisions of Technical Management Regulations for Railway more accurately,so as to better serve the comprehensive revision of the Regulations,this paper carries out the research on the traceability and evolution of the provisions of the Regulations.Design/methodology/approach–This paper studies and analyzes the evolution of the 11th edition of the Regulations by analyzing the relevance of clauses and summarizes the historical background of the development of calendar editions of the Regulations.The basic research on the traceability and evolution of the Regulations is carried out from four aspects:the continuity of the development of the Regulations,the authority of contents,the relevance of clauses and the richness of historical materials.Findings–From the first edition of the Regulations issued by the former Ministry of Railways in 1950 to the 11th edition,there have been ten comprehensive revisions.There is a strong correlation and continuity between the calendar editions of the Regulations in terms of chapter structure and clauses.Studying the context of the terms of the Regulations is an important way to understand and master the current clauses of the Regulations.Originality/value–Through the research on the traceability and evolution of the clauses of the Regulations,one is to explore the context of the development of railway technical equipment in China,the other is to clarify the historical background when the provisions were formulated and the third is to trace the development and evolution of the provisions.The revision of the Regulations is based on an accurate grasp of the context of the provisions,which can effectively judge the possible security risks caused by the revision of the provisions and avoid the possible risks in field implementation from the source. 展开更多
关键词 technical management regulations for railway Origin and evolution REVISION technical regulation Organization of train operation
下载PDF
Correlation Analysis between Self-Disclosure and Social Support in Patients with Breast Cancer
16
作者 Yun Ding Liping Zhang +1 位作者 Huiying Qin Lijuan Zhang 《Advances in Breast Cancer Research》 CAS 2024年第4期59-68,共10页
Objective: Describe the status quo of self-disclosure and social support in breast cancer patients and analyze the correlation between them. Methods: General data questionnaire, distress disclosure Index scale and Chi... Objective: Describe the status quo of self-disclosure and social support in breast cancer patients and analyze the correlation between them. Methods: General data questionnaire, distress disclosure Index scale and Chinese version of medical social support scale were used to investigate the correlation between self-disclosure and social support in breast cancer patients by Pearson correlation analysis. Results: 1) The total self-disclosure score was (38.75 ± 9.18);the total score of social support was (70.57 ± 14.04) scores, including emotional information support dimension (28.39 ± 6.06) scores, practical support dimension (15.62 ± 3.31) scores, elastic support dimension (14.85 ± 3.23) scores, and emotional support dimension (11.70 ± 2.56) scores. 2) Self-disclosure was positively correlated with social support (r = 0.433, p Conclusion: Breast cancer patients had a moderate level of self-disclosure, and the higher the level of self-disclosure, the better the social support. It is suggested that improving the self-disclosure level of breast cancer patients can help them obtain more social support. 展开更多
关键词 Breast Cancer SELF-DISCLOSURE Social support
下载PDF
Cost-effective bifunctional lignin-derived carbon supported tin oxide with efficient production of 5-hydroxymethylfurfural from glucose
17
作者 Sien Yan Linhuo Gan +1 位作者 Kui Wang Kang Sun 《Chinese Journal of Chemical Engineering》 SCIE EI CAS CSCD 2024年第10期154-164,共11页
5-Hydroxymethylfurfural(5-HMF)is one of the important bio-based platform compounds,and the catalytic conversion of glucose to 5-HMF is a highly desirable approach that is receiving increasing attention.Herein,we repor... 5-Hydroxymethylfurfural(5-HMF)is one of the important bio-based platform compounds,and the catalytic conversion of glucose to 5-HMF is a highly desirable approach that is receiving increasing attention.Herein,we reported the synthesis of lignin-derived carbon supported tin oxides(SnOx/LC)catalyst via a two-step hydrothermal-pyrolytic method using wheat straw alkali lignin as a cost-effective carbon source with high carbon content.The key preparation conditions of the catalyst and its catalytic conditions for the conversion of glucose to 5-HMF were investigated,respectively.Results show that under the preparation conditions of tin tetrachloride dosage of 3.0 mmol and pyrolysis temperature of 500 ℃,the optimized catalyst(3.0-SnOx/LC-500)with a high yield of 63.4%exhibits good catalytic performance of 5-HMF yield of 50.1%and reaction selectivity of 86.0%under the optimum conditions of reaction temperature and time of 190 ℃ and 3 h,initial glucose concentration of 10%(mass),3.0-SnOx/LC-500 dosage of 100 mg in a biphasic solvent system of volume ratio of water to tetrahydrofuran of 1:4.In addition,3.0-SnOx/LC-500 exerts an excellent reusability in a five-cycle experiment.Furthermore,SnOx/LC was characterized in detail using X-ray diffraction patterns(XRD),X-ray photoelectron spectroscopy(XPS),Brunauer-Emmett-Teller(BET),ammonia temperature-programmed-desorption(NH3-TPD),pyridine adsorption infrared spectroscopy(Py-FTIR),scanning electron microscope(SEM)and thermal gravimetric analysis(TGA).Results indicate that Brønsted acid sites and Lewis acid sites coexist on 3.0-SnOx/LC-500,and more Sn^(4+),as well as a proper ratio of weak acidity to medium acidity,are conductive to its catalytic performance in glucose-to-5-HMF reaction. 展开更多
关键词 LIGNIN Biomass Catalyst support SELECTIVITY Biphasic solvent system
下载PDF
Adhesion of Technical Lignin-Based Non-Isocyanate Polyurethane Adhesives for Wood Bonding
18
作者 Jaewook Lee Byung-Dae Park Qinglin Wu 《Journal of Renewable Materials》 EI CAS 2024年第7期1187-1205,共19页
Lignin is the most abundant aromatic natural polymer,and receiving great attention in replacing various petro-leum-based polymers.The aim of this study is to investigate the feasibility of technical lignin as a polyol... Lignin is the most abundant aromatic natural polymer,and receiving great attention in replacing various petro-leum-based polymers.The aim of this study is to investigate the feasibility of technical lignin as a polyol for the synthesis of non-isocyanate polyurethane(NIPU)adhesives to substitute current polyurethane(PU)adhesives that have been synthesized with toxic isocyanate and polyols.Crude hardwood kraft lignin(C-HKL)was extracted from black liquor from a pulp mill followed by acetone fractionation to obtain acetone soluble-HKL(AS-HKL).Then,C-HKL,AS-HKL,and softwood sodium lignosulfonate(LS)were used for the synthesis of technical lignin-based NIPU adhesives through carbonation and polyamination and silane as a cross-linker.Their adhesion per-formance was determined for plywood.FTIR spectra showed the formation of urethane bonds and the reaction between lignin and silane.The NIPU adhesives prepared with C-HKL showed the highest adhesion strength among the three lignin-based NIPU adhesives.As the silane addition level increased,the adhesion strength of NIPU adhesives increased whereas formaldehyde emission decreased for all NIPU adhesives prepared.These results indicate that NIPU adhesives based on technical kraft lignin have a great potential as polyol for the synth-esis of bio-based NIPU adhesives for wood bonding. 展开更多
关键词 technical lignin non-isocyanate polyurethane wood adhesives adhesion strength formaldehyde emission
下载PDF
Technical efficiency of cocoa farms at varying elevation levels in Davao City, Philippines: implications to sustainable upland farming systems
19
作者 Francis Levi A.DURANO Jon Marx SARMIENTO +1 位作者 Larry N.DIGAL Pedro A.ALVIOLA IV 《Journal of Mountain Science》 SCIE CSCD 2024年第1期33-48,共16页
Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa ... Elevation is one of many components that influence agriculture, and this in turn affects the level of both inputs and outputs of farmers. This article focuses on the productivity and technical efficiency of 100 cocoa farms using cross-sectional data from areas ranging from 190 to 1021 m above sea level which were classified as low, medium, and high elevation in Davao City, considered as the chocolate capital of the Philippines. Using stochastic frontier analysis, the results showed that the cost of inputs per ha and the number of cocoa trees per ha significantly increase yield. Farms at high elevations were less technically efficient, as this entails lower temperatures and increased rainfall, and cocoa farming in those areas and conditions can be more challenging, especially with changes in farming practices, terrain, and distance to markets. Other significant variables were age of cocoa farms, married farmers, and age of the farmers. Older farms may be more developed, farmers who are married benefit from their spouses being able to readily contribute as farm labor, and lastly, older farmers' inefficiency may likely stem from nonadaptation of newer farming practices. With an average technical efficiency of 0.61, 0.63, and 0.26 in low, medium, and high elevation areas, respectively, farmers therefore have an incentive to improve farm practices and consider topographical variations found in high elevation areas. Recommendations for the improvement of technical efficiency of cocoa farms are better connectivity to markets, enhancing farm practices, and continuation and improvement of government programs on cocoa with an added emphasis on research. For farmers in high elevation areas, mitigating solutions such as sustainable agriculture practices and ecolabelling are key to improving efficiency and minimizing the potential negative impact on upland farming systems. Moreover, such adaptation measures may also contribute to sustainability of cocoa farming in high elevation areas. 展开更多
关键词 Cocoa farms Cobb-Douglas production function ELEVATION Philippines Stochastic frontier analysis technical efficiency
下载PDF
Perspectives and Challenges of Family Members in Providing Mental Support to Cancer Patients:A Qualitative Study in Beijing,China
20
作者 Wei Wang Lan Li 《Psycho-Oncologie》 SCIE 2024年第4期257-269,共13页
This study explores the perspectives and challenges faced by family members providing mental support to cancer patients in Beijing,China.The primary objective is to understand the emotional and practical roles family ... This study explores the perspectives and challenges faced by family members providing mental support to cancer patients in Beijing,China.The primary objective is to understand the emotional and practical roles family members undertake and the difficulties they encounter.Utilizing a qualitative research design,data were collected through semi-structured interviews with family caregivers of cancer patients.Thematic analysis revealed several key themes:the dual burden of emotional support and caregiving responsibilities,the impact on daily life and personal well-being,the role and effectiveness of external support systems,perceptions of medical staff support,and the common challenges and conflicts faced in caregiving.The findings highlight the critical need for comprehensive support systems that address both the emotional and practical needs of family caregivers.Recommendations for enhancing family-centered support programs in oncology settings are discussed. 展开更多
关键词 Family caregivers mental health support cancer patients qualitative study BEIJING caregiving challenges emotional support healthcare systems
下载PDF
上一页 1 2 250 下一页 到第
使用帮助 返回顶部