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Fretting wear behaviour of high-nitrogen stainless bearing steel under lubrication condition

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Journal of Iron and Steel Research International 2020年第7期27卷 849-866页

作者： Huan Lin Mao-sheng Yang Bai-po Shu College of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093YunnanChina Institute for Special Steel Central Iron and Steel Research InstituteBeijing 100081China

The fretting wear performance of high-nitrogen stainless bearing steel(40Cr15Mo2VN)under lubrication conditions was ***-based grease was preparedusing MoS2 and carbon nanotubes(CNTs)as *** 52100 steel ball was used in four-ball test to evaluate the extreme pressure property and wear resistance of *** four-ball test,the grease adding 0.8 mass%MoS2 and 0.8 mass%CNTs,respectively,was chosen and used for fretting *** 52100 ball and 40Cr15Mo2VN steel disc were used as the upper and lower samples for fretting *** results showed that wear power consumption increased with the increase in both sliding velocity and contact *** initial contact stress was 2.047 GPa,the main wear mechanisms were abrasive wear and plastic deformation as the velocity increased 0.028 to 0.112 m/*** the velocity was 0.028 m/s,the main wear mechanisms changed abrasive wear to adhesion wear and finally to abrasive wear and adhesion wear as the initial contact stress increased 1.788 to 2.579 *** volume loss grew sharply becaof the changes in wear *** this condition,the volume loss growth rate can be divided into three regions according to different wear power consumption ranges corresponding to different wear mechanisms.

关键词： High-nitrogen steel Sliding velocity Contact stress Adhesion wear Abrasive wear Wear power consumption

Control of petroleum-hydrocarbon contaminated groundwater by intrinsic and enhanced bioremediation

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Journal of Environmental Sciences 2010年第6期22卷 864-871页

作者： Chih-Ming kao Rao Y.Surampalli Mu-sheng Lee Institute of Environmental Engineering "National" Sun Yat-Sen University U.S.Environmental Protection Agency Environmental Protection Bureau Kaohsiung City Government

In the first phase of this study, the effectiveness of intrinsic bioremediation on the containment of petroleum hydrocarbons was evaluated at a gasoline spill site. Evidences of the occurrence of intrinsic bioremediation within the BTEX （benzene, toluene, ethylbenzene, and xylenes） plume included （1） decreased BTEX concentrations; （2） depletion of dissolved oxygen （DO）, nitrate, and sulfate; （3） production of dissolved ferrous iron, methane, and CO2; （4） deceased pH and redox potential; and （5） increased methanogens, total heterotrophs, and total anaerobes, especially within the highly contaminated areas. In the second phase of this study, enhanced aerobic bioremediation process was applied at site to enhance the BTEX decay rates. Air was injected into the subsurface near the mid-plume area to biostimulate the naturally occurring microorganisms for BTEX biodegradation. Field results showed that enhanced bioremediation process caused the change of BTEX removal mechanisms from anaerobic biodegradation inside the plume to aerobic biodegradation. This variation could be confirmed by the following field observations inside the plume due to the enhanced aerobic bioremediation process：（1） increased in DO, CO2, redox potential, nitrate, and sulfate, （2） decreased in dissolved ferrous iron, sulfide, and methane, （3） increased total heterotrophs and decreased total anaerobes. Field results also showed that the percentage of total BTEX removal increased from 92% to 99%, and the calculated total BTEX first-order natural attenuation rates increased from 0.0092% to 0.0188% per day, respectively, after the application of enhanced bioremediation system from the spill area to the downgradient area （located approximately 300 m from the source area）.

关键词： petroleum hydrocarbon groundwater natural attenuation intrinsic bioremediation

Uncommon complication of nasoenteral feeding tube:A case report

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World Journal of Clinical Cases 2022年第5期10卷 1598-1601页

作者： Yong-po Jiang sheng Zhang Rong-Hai Lin Department of Critical care medicine Taizhou Hospital of Zhejiang Province affiliated to Wenzhou Medical UniversityTaizhou 317000Zhejiang ProvinceChina

BACKGROUND The jejunal nutrition tube has increasingly been used in clinical practice,and the results in frequent *** SUMMARY We present the case of a 74-year-old male patient who had been admitted to the intensive care unit for aspiration pneumonia and respiratory *** confirming the position of the jejunal tube by X-ray,we found that the feeding tube had been placed into the *** complications was a disaster,though the misplacement of jejunal feeding tube are *** We introduced a way of ultrasound-guided jejunum feeding tube placement to avert the disaster,which was convenient and economical.

关键词： Nasoenteral feeding tube Nutritional support Complication Ultrasoundguided Feeding tube placement Case report

In Situ/Operando(Soft) X-ray Spectroscopy Study of Beyond Lithium-ion Batteries

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Energy & Environmental Materials 2021年第2期4卷 139-157页

作者： Feipeng Yang Xuefei Feng Yi-sheng Liu Li Cheng kao Per-Anders Glans Wanli Yang Jinghua Guo Joint Center for Energy Storage Research Lemont IL 60439USA Advanced Light Source Lawrence Berkeley National LaboratoryBerkeley CA 94720USA Department of Chemistry and Biochemistry University of California Santa CruzSanta Cruz CA 95064USA

The lightweight,rechargeable lithium-ion battery is one of the dominant energy storage devices globally in portable electronics due to its high energy density,no memory effect,wide operating voltage,lightweight,and good charge ***,due to safety concerns,the depletion of lithium reserves,and the corresponding increase of cost,an alternative battery system becomes more and more *** develop alternative battery systems with low cost and high material abundance,for example,sodium,magnesium,zinc,and calcium,it is important to understand the chemical and electronic structure of *** X-ray spectroscopy,for example,X-ray absorption spectroscopy(XAS),X-ray emission spectroscopy(XES),and resonant inelastic soft X-ray scattering(RIXS),is an element-specific technique with sensitivity to the local chemical environment and structural order of the element of *** soft X-ray systems enable operando experiments that can be applied to amorphous and crystalline samples,making it a powerful tool for studying the electronic and structural changes in electrode and electrolyte *** this article,the application of in situ/operando(soft)X-ray spectroscopy in beyond lithium-ion batteries is reviewed to demonstrate how such spectroscopic characterizations could facilitate the interpretation of interfacial phenomena under in situ/operando condition and subsequent development of the beyond lithium-ion batteries.

关键词： (soft)X-ray spectroscopy beyond lithium-ion battery in situ/operando interface

Primary leiomyosarcoma of the nipple-areola complex:Report of a case and review of literature

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第2期9卷 109-113页

作者： Lai-ching WONG po-chi HUANG Shi-ping LUH Chiun-sheng HUANG Department of Pathology Taichung Hospital Executive Yuan Department of Health Taichung 401 Taiwan China Department of Surgery Chung-Shan Medical University and Hospital Taichung 402 Taiwan China Department of Surgery National Taiwan University Hospital Taipei 100 Taiwan China

Primary leiomyosarcoma of the nipple-areola complex is extremely rare. Less than ten such cases have been reported in English literature so far. Herein we describe a 52-year-old female presenting with a 1.5 cm×1.1 cm×0.7 cm nodular lesion over her left nipple, and leiomyosarcoma was proved by pathological examination of the excised specimen. positron emitted tomogram (PET) revealed no abnormal signal other than the primary site. Microscopically, this poorly circumscribed tumor was composed of interlacing bundles of smooth muscle cells with bizarre and pleomorphic nuclei, as well as prominent nucleoli. Its mitotic count was up to 7 mitoses per 10 high power fields (HPF). Immunohistochemical study of tumor cells revealed positive stain for α-smooth muscle actin and vimentin; and negative for cytokeratin, CD34 and S-100. Left simple mastectomy was undertaken and no residual mass lesion was noted on the resected specimen. Related literatures about the diagnosis and treatment for breast leiomyosarcoma will be presented here.

关键词： Breast Leiomyosarcoma Mastectomy

NUMERICAL SIMULATION OF BATOID LOCOMOTION

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Journal of Hydrodynamics 2011年第5期23卷 594-600页

作者： CHEN Wei-shan WU Zhi-jun LIU Jun-kao SHI sheng-jun ZHOU Yang State Key Laboratory of Robotics and System Harbin Institute of Technology Harbin 150001 China

The hydrodynamics of batoid swimming motions is investigated using the three-dimensional simulation of a self-propelled body in still water. The kinematics of batoid swimming is characterized by large amplitude undulations of the pectoral fins while the middle part of the body remains straight. The majority of the thrust is generated by pectoral fins. Linear and quadratic amplitude variations are used for the pectoral fins in analyzing the locomotion of the batoid. Navier-Stokes equations are used to solve the unsteady fluid flow. A user defined function and a dynamic mesh method are applied to track the batoid locomotion. The mean swimming velocities of 1.6 BL/s and 1.3 BL/s are achieved, respectively, with thrust coefficients of 0.13 in and 0.095 in the dynamical simulation, where BL/s is the body length per second. The maximum propulsive efficiency 19% is achieved when the frequency of the undulation is 2.2 Hz in both amplitude variations.

关键词： batoid fish undulation pectoral fin dynamical simulation

Chemical constituents from the leaves of Cerbera manghas

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Asian Pacific Journal of Tropical Medicine 2010年第2期3卷 109-111页

作者： Zhang Xiao-po Pei Yue-hu Liu Ming-sheng Kang sheng-li Zhang Jun-qing Department of Pharmacy Hainan Medical College School of Traditional Chinese Materia Media Shenyang Pharmaceutical University Hainan Provincial Institute of South China Medicine and Li Nationality Medicine

Objective:To study the chemical constituents in leaves of Cebera ***:Chemical constituents were isolated by using various column chromatography and tho structures were elucidated on basis of physicochemical constants and spectral data ***:Nine compounds were obtained including p-hydroxybenzaldehyde(1),benzamide(2),n-hexadecane acid monoglyceride(3),loliolide(4),β-sitosterol(5),cerberin(6),neriifolin(7),cerleaside A(8), daucosterol(9).Conclusions:Compounds 1-4 are obtained from this genus for the first time.

关键词： Cerbera manghas L. Li Nationality Medicine Chemical constituents

Effects of Crop Development on the Emission of Volatiles in Leaves of Lycopersicon esculentum and Its Inhibitory Activity to Botrytis cinerea and Fusarium oxysporum

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Journal of Integrative Plant Biology 2008年第1期50卷 84-91页

作者： Peng-Ying Zhang kao-Shan Chen Pei-Qing He sheng-Hao Liu Wan-Feng Jiang College of Life Sciences Shandong University Jinan 250100 China Key Laboratory of Marine Bioactive Substances First Institute of Oceanography State Oceanic Administration Qingdao 266061 China Qingdao Quafity Supervision and Inspection Center for Shopping Basket Commodity Qingdao 266003 China

Volatiles emitted from the leaves of Lycopersicon esculentum at the two-, ten-leaf and anthesis periods were collected by a gas absorbing method and analyzed by gas chromatography （GC）-mass spectrometry. In total, 33 compounds of volaUles emitted from three developmental stage plants were separated and identified, and quantitatively analyzed by the internal standard addition method. All of the samples of volatile were found to be rich in monoterpenes and sesquiterpenes.β-phellandrene and caryophyllene predominated in the volatiles of the leaves of plants at the two- and ten-leaf stages. Furthermore, （E）-2-hexenal were the dominant components in the volatiles emitted from anthesis plants. The results of volatiles analyzed show that the compositions varied depending on the developmental stages. The volatiles emitted from crushed tomato leaves of plants at the anthesis stage had the most strongly inhibitory activity against the spore germination and hyphal growth of Botrytis cinerea and Fusarium oxysporum, followed by ten- and two-leaf plants. However, the activity of volatiles, emitted from the leaves of plants at the two-leaf stage, in inhibiting F. oxysporum was greater than B. cinerea.

关键词： development inhibitroy activity Lycopersicon esculentum volatiles.

On the initiation,movement and deposition of a large landslide in Maoxian County,China

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Journal of Mountain Science 2018年第6期15卷 1319-1330页

作者： pei xiang-jun guo bin cui sheng-hua wang dong-po xu qiang li tian-tao State Key Laboratory of Geohazard Prevention and Geoenvironment Protection Chengdu University of Technology Chengdu 610059 China

At 5 am 24 th June 2017, a catastrophic landslide hit Xinmo Village, Maoxian County, Sichuan Province, China. The slide mass rushed down from an altitude of 3400 m and traveled 2700 m in a high velocity. The 13 million m^3 deposition buried the whole village and caused about 100 deaths. The source area of the landslide is located in a high steep slope, average slope angle is 40o and maximal angle is 65o. The strata are interbedded Triassic Zagunao Formation metamorphic sandstone and slate with the dip slope angle of 45°. Based on high-resolution satellite remote sensing image, UAV image, DEM data, and field investigation, failure mechanism, travel features, and deposit characteristics were analyzed. The results showed that this landslide was influenced by Songpinggou Fault zone. According to the topography before the failure, the landslide is located in the back scarp of an antecedent landslide induced by Diexi Earthquake in 1933. The bedding slope provided potential rupture surface. Historical seismic activities and long-term gravitational deformation caused rock mass accumulated damages. Weathering and precipitation weakened the rock mass and finally induced shearing and tension failure. A huge block detached from the top rock slope, pushed the past landslide deposits in the middle part, rushed out of the slope bottom in a high velocity and buried the Xinmo Village. The rapid movement entrained and brought the soil into the Songping Gully which recoiled with and bounced back from the opposite mountain.

关键词： Xinmo landslide Seismic damages Longrunout Failure mechanism Rock fragment