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High-temperature corrosion of sintered RE_(2)Si_(2)O_(7)(RE=Yb and Ho)environmental barrier coating materials by volcanic ash

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International Journal of Minerals,Metallurgy and Materials 2024年第7期31卷 1628-1638页

作者： Ayahisa Okawa son Thanh Nguyen Tadachika Nakayama Thi-mai-Dung Do Hisayuki Suematsu Shu Yin Takuya Hasegawa Tsuneo Suzuki Takashi Goto Koichi Niihara Institute of Multidisciplinary Research for Advanced Materials Tohoku UniversitySendai 980-8577Japan Department of Creative Engineering National Institute of TechnologyKushiro 084-0916Japan Extreme Energy-Density Research Institute Nagaoka University of TechnologyNagaoka 940-2188Japan Advanced Institute for Materials Research(WPI-AIMR) Tohoku UniversitySendai 980-8577Japan

Rare-earth silicates are promising environmental barrier coatings(EBCs)that can protect SiC_(f)/Si C_(m)substrates in next-genera tion gas turbine ***,RE_(2)Si_(2)O_(7)(RE=Yb and Ho)shows potential as an EBC due to its coefficient of thermal expansion(CTE)compatible with substrates and high resistance to water vapor *** target operating temperature for next-generation tur bine blades is 1400°*** is inevitable during adhesion to molten volcanic ash,and thus,understanding the corrosion behavior o the material is crucial to its *** study investigates the high-temperature corrosion behavior of sintered RE_(2)Si_(2)O_(7)(RE=Yb and Ho).Samples were prepared using a solid-state reaction and hot-press *** were then exposed to volcanic ash at 1400°C for 224,and 48 *** 48 h of exposure,volcanic ash did not react with Yb_(2)Si_(2)O_(7)but penetrated its interior,causing *** Ho_(2)Si_(2)O_(7)was partially dissolved in the molten volcanic ash,forming a reaction zone that prevented volcanic ash melts from penetrating the *** increasing heat treatment time,the reaction zone expanded,and the thickness of the acicular apatite grains increased The Ca:Si ratios in the residual volcanic ash were mostly unchanged for Yb_(2)Si_(2)O_(7)but decreased considerably over time for Ho_(2)Si_(2)O_(7).Th Ca in volcanic ash was consumed and formed apatite,indicating that RE^(3+)ions with large ionic radii(Ho>Yb)easily precipitated apatit from the volcanic ash.

关键词： environmental barrier coating volcanic ash rare-earth disilicate corrosion

Oxygen functionalization-assisted anionic exchange toward unique construction of flower-like transition metal chalcogenide embedded carbon fabric for ultra-long life flexible energy storage and conversion

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Carbon Energy 2024年第1期6卷 72-93页

作者： Roshan M.Bhattarai Kisan Chhetri Nghia le Debendra Acharya Shirjana Saud mai Cao Hoang Phuong Lan Nguyen Sang Jae Kim Young Sun Mok Department of Chemical Engineering Jeju National UniversityJejuRepublic of Korea Department of Nano Convergence Engineering Jeonbuk National UniversityJeonjuRepublic of Korea Regional leading Research Center(RLRC)for Nanocarbon-based Energy Materials and Application Technology Jeonbuk National UniversityJeonjuRepublic of Korea Department of Chemistry Mississippi State UniversityStarkvilleMississippiUSA Nanomaterials and System Laboratory Department of Mechatronics EngineeringJeju National UniversityJejuRepublic of Korea

The metal-organic framework(MOF)derived Ni–Co–C–N composite alloys(NiCCZ)were“embedded”inside the carbon cloth(CC)strands as opposed to the popular idea of growing them upward to realize ultrastable energy storage and conversion *** NiCCZ was then oxygen functionalized,facilitating the next step of stoichiometric sulfur anion diffusion during hydrothermal sulfurization,generating a flower-like metal hydroxysulfide structure(NiCCZOS)with strong partial implantation inside *** obtained NiCCZOS shows an excellent capacity when tested as a supercapacitor electrode in a three-electrode ***,when paired with the biomass-derived nitrogen-rich activated carbon,the asymmetric supercapacitor device shows almost 100%capacity retention even after 45,000 charge–discharge cycles with remarkable energy density(59.4 Wh kg^(-1)/263.8μWh cm^(–2))owing to a uniquely designed ***,the same electrode performed as an excellent bifunctional water-splitting electrocatalyst with an overpotential of 271 mV for oxygen evolution reaction(OER)and 168.4 mV for hydrogen evolution reaction(HER)at 10 mA cm−2 current density along with 30 h of unhinged chronopotentiometric stability performance for both HER and ***,a unique metal chalcogenide composite electrode/substrate configuration has been proposed as a highly stable electrode material for flexible energy storage and conversion applications.

关键词： carbon cloth energy conversion energy storage flexible metal embedding ultra-stable

Exploring the Interplay between Job Stress,Work Performance,and Attitudes toward Professional Psychological Help among Employees

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International Journal of Mental Health Promotion 2024年第7期26卷 531-545页

作者： Cong Minh le son Van Huynh Ky Luu Quynh-Nhi Ngoc Ho Van Thi le Nguyen Vinh-Long Tran-Chi Center for Mental Health Research and Support University of Social Sciences and HumanitiesVietnam National University Ho Chi Minh CityHo Chi Minh City700000Vietnam Faculty of Psychology Ho Chi Minh City University of EducationHo Chi Minh City700000Vietnam Faculty of Tourism College of BusinessUniversity of Economics Ho Chi Minh CityHo Chi Minh City700000Vietnam Scientific Management Department Dong A UniversityDa Nang500000Vietnam

Objective:This study explores the interplay between job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese ***:A total of 374 employees in Vietnam were surveyed using random sampling and an online questionnaire from November 07 to November 28,*** data and self-reported from three scales:The New Job Stress Scale(NJSS),Work Performance(WP),and Attitudes Toward Seeking Professional Psychological Help(ATSPPH_SF)were ***:Significant variations were found across several variables,including forms of work,operating hours,education levels,monthly income,numbers of daily working hours,and the presence of a psychological counseling department within the *** analysis has highlighted direct relationships between key latent *** who were more open to seeking professional help tended to report higher levels of job *** negative relationship was found between job stress and attitudes toward seeking professional ***,work effort was positively associated with work *** analyses revealed the influence of co-worker support on role expectation conflict and work effort,role expectation conflict and work-life balance,as well as interactions between role expectation conflict and attitudes needed toward seeking professional *** analyses showed that work effort mediated relationships between openness to seeking professional help,co-worker support,work-life balance,role expectation conflict,and work *** toward seeking professional help also mediated relationships between work-life balance,job stress,and work ***:The study highlights the complex dynamics surrounding job stress,job-related factors,work performance,and attitudes toward seeking professional psychological help among Vietnamese *** highlights the importance of addressing help-seeking barriers,promoting work engagement

关键词： Stress co-worker support work-life balance role expectation conﬂict professional psychological help-seeking

新型农业经营主体生存动态演化的时空格局及其影响因素

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地理科学进展 2024年第1期43卷 47-62页

作者：麦强盛李乐西南林业大学会计学院昆明650233 西南林业大学经济管理学院昆明650233

研判新型农业经营主体发展的外部环境、内生动力和演化趋势,增强农业农村发展新动能,是关系中国农业农村现代化的重大战略。论文基于2000—2022年农业农村部公布的农业产业化国家重点龙头企业、全国农民合作社和家庭农场典型案例名单以... 详细信息

研判新型农业经营主体发展的外部环境、内生动力和演化趋势,增强农业农村发展新动能,是关系中国农业农村现代化的重大战略。论文基于2000—2022年农业农村部公布的农业产业化国家重点龙头企业、全国农民合作社和家庭农场典型案例名单以及中国农业企业黄页中的新型农业经营主体相关数据,通过空间计量分析和生存分析,探究其生存的空间格局及其影响因素。研究发现:①新型农业经营主体进入和退出农业市场的数量呈现倒“U”型曲线,实存数量呈逐渐上升的状态。②新型农业经营主体的生存时间在区域间形成差异化格局,高—高集聚区主要集中在中东部地区。③“个体特征和创新能力”因素对新型农业经营主体生存时间有正向影响,“阶段演变”对其生存时间有负向影响。④随着成立阶段的推移,新型农业经营主体资产规模和关联经济组织数量对其生存时间的影响作用逐渐下降,地理区域因素影响作用也逐渐减弱。研究结论可为新型农业经营主体生存分析提供实证依据,为分析其发展演化的地理特征提供借鉴参考。

关键词：新型农业经营主体生存时间时序格局阶段演变

Estimation of Tropical Forest Structural Characteristics Using ALOS-2 SAR Data

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Advances in Remote Sensing 2016年第2期5卷 131-144页

作者： Luong Viet Nguyen Ryutaro Tateishi Hoan Thanh Nguyen Ram C. Sharma Tu Trong To son mai le Center for Environmental Remote Sensing Chiba University Chiba Japan Space Technology Institute Vietnam Academy of Science and Technology Hanoi Vietnam Institute of Geography Vietnam Academy of Science and Technology Hanoi Vietnam

The potential of ALOS-2 SAR data for the estimation of tropical forest structural characteristics was assessed in Vietnam by collecting forest inventory data. The effect of polarization and seasonality of the SAR data on the estimation of forest biomass was analyzed. The combination of HH, HV, and HH/HV polarizations using multiple linear regression did not improve the estimation of biomass compared to using the HV channel independently, as the HH and HH/HV variables were not statistically significant. The dry season HV backscattering intensity was highly sensitive to the biomass compared to the rainy season backscattering intensity. The SAR data acquired in the rainy season with humid and wet canopies was not very sensitive to the biomass. The strong dependence of the biomass estimates with the season of SAR data acquisition confirmed that the choice of right season SAR data is very important for improving the satellite based estimates of the biomass. The validation results showed that the dry season HV polarization could explain 54% variation of the biomass.

关键词： Forest Structure Forest Biomass SAR ALOS-2 Backscattering Intensity Sensitivity Analysis

New application of intestinal obstruction catheter in enterocutaneous fistula:A case report

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World Journal of Clinical Cases 2024年第20期12卷 4384-4390页

作者： Xiao-Tong Wang Long Wang An-Lin Liu Jing-le Huang lei Li Zhi-Xing Lu Wei mai Departments of Gastrointestinal Hernia and Enterofistula SurgeryPeople's Hospital of Guangxi Zhuang Autonomous Region&Institute of Minimally Invasive Technology and ApplicationsNanning 530021Guangxi Zhuang Autonomous RegionChina

BACKGROUND Enterocutaneous fistula(ECF)is an abnormal connection between the gastrointestinal tract and the *** can lead to massive body fluid loss,hypercatabolism,and ***,nutritional support plays a crucial role in managing ECFs and promoting the healing of *** nutritional support,enteral nutrition(EN)is the preferred method when gastrointestinal function is ***,various EN approaches have been applied for different anatomical positions of the ***,the effectiveness of administering EN support for treating lower ECFs still needs further exploration and *** SUMMARY We present the case of a 46-year-old male who underwent gastrointestinal stromal tumour *** days after the surgery,the patient presented with fever,fatigue,severe upper abdominal pain,and septic ***,lower ECFs were diagnosed through laboratory and imaging *** addition to symptomatic treatment for homeostasis,total parenteral nutrition support was administered in the first 72 h due to dysfunction of the *** that,we gradually provided EN support through the intestinal obstruction catheter in consideration of the specific anatomic position of the fistula instead of using the nasal jejunal ***,the patient could receive optimal EN support via the catheter,and no complications were found during the *** Nutritional support is a crucial element in ECF management,and intestinal obstruction catheters could be used for early EN administration.

关键词： Enterocutaneous fistula Intestinal obstruction catheter Nutritional support Enteral nutrition pathway Case report

Velocity equation for grenades while impacting on dry sand media

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Defence Technology（防务技术） 2024年第5期35卷 168-173页

作者： Martin Macko Xuan son Bui Kongsathit Phanthavong Duc Hung Pham Van Gion Do Van Minh Do Jiri Skala University of Defence BrnoCzech Republic le Quy Don Technical University Ha NoiViet Nam

This paper deals with the collision of sphere shape grenades with sand *** central issue of the article is the establishing of an empirical velocity equation of the grenade while impacting on sand that is used to solve motion equations of the mechanical mechanism inside the impact grenade *** paper focuses on impact velocities that are lower than 5 m s^(-1).An experiment was conducted to study the velocity of the grenade while impacting on dry sand.A high-speed camera video was used to capture the grenade *** grenade velocity in the impact process was generated from these video *** types of fitting curves are used to regress the velocity equation of the grenade while interacting with the sand media and the best-fitting model is *** result shows the regression curve has a high correlation with the experiment data for grenade velocities below 5 m s^(-1).The received regression equation is useful for analyzing the working ability of the inertial mechanism inside the impact grenade or analyzing and choosing the appropriate parameters of each part in the inertial mechanism to meet the required characteristics of the mechanism.

关键词： Dynamic response Impact velocity Impact grenade Low-velocity impact

Dry eye rate and its relationship with disease stage in patients with primary hypertension:a cross-sectional study in Vietnam

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International Journal of Ophthalmology(English edition) 2024年第4期17卷 653-658页

作者： Tran Tat Thang Pham Hong Phuong Nguyen Sa Huynh Nguyen Trung Kien NguyenDuy Toan Nguyen Thi Thu Ha le Ha Khoa Nguyen Huu Dung Thai Doan Thang le Viet Thang Nghe An Eye Hospital Nghe An 43000Vietnam Nghe An Friendship General Hospital Nghe An 43000Vietnam Military Hospital 103 Ha Noi 100000Vietnam Vietnam Military Medical University Ha Noi 100000Vietnam Hanoi Medical University Ha Noi 100000Vietnam Bạch mai Hospital Ha Noi 100000Vietnam TTH Vinh General Hospital Nghe An 100000Vietnam

AIM:To determine the dry eye(DE)rate and its relationship with disease stage in patients with primary ***:A cross-sectional study included 432 patients with primary hypertension(with an equal number of patients in each group:144 in stage Ⅰ,Ⅱ,and Ⅲ hypertension)and 144 healthy subjects as a control *** Ocular Surface Disease Index(OSDI)and Schirmer Ⅰ test without anesthetics were conducted on all 576 *** with OSDI scoreslevels in hypertension patients with DE were higher than those without DE,Plevated plasma creatinine,and CRP-hs levels were independent factors associated with DE in primary hypertension patients,Plevated plasma CRP-hs,and creatinine levels in patients with primary hypertension.

关键词： primary hypertension dry eye stage of hypertension plasma creatinine

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植物环肽研究进展

中国中药杂志 2024年第5期49卷 1172-1185页

作者：赵冕王磊冯子迈蔡乐贾庆忠河北医科大学教学实验中心河北石家庄050017 河北医科大学药学院河北石家庄050017 云南大学化学科学与工程学院云南昆明650091

植物环肽是一类主要由氨基酸肽键形成的环状含氮化合物,一般包含2~37个L-构型的编码或者非编码氨基酸结构单元,是具有重要研究价值的天然植物小分子代谢产物。科学研究表明,此类天然产物在各科植物中广泛分布,化学成分主要包括环二肽类... 详细信息

植物环肽是一类主要由氨基酸肽键形成的环状含氮化合物,一般包含2~37个L-构型的编码或者非编码氨基酸结构单元,是具有重要研究价值的天然植物小分子代谢产物。科学研究表明,此类天然产物在各科植物中广泛分布,化学成分主要包括环二肽类、环四肽类、环五肽类、环六肽类、环七肽类、环八肽类、环九肽类、环十肽类等,其中环二肽类、环六肽类、环八肽类是其主要活性成分。据报道,植物环肽结构新奇、独特,具有抗肿瘤、抗菌、抗疟、抗炎、抗病毒等多种药理活性。该文对2006年以来植物环肽的研究成果进行了综述,以期为植物环肽及其在相关医药、卫生、农业等领域的进一步研究提供理论参考。

关键词：植物环肽化学成分药理活性