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Discontinuity development patterns and the challenges for 3D discrete fracture network modeling on complicated exposed rock surfaces 被引量:1
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作者 Wen Zhang Ming Wei +8 位作者 Ying Zhang Tengyue Li Qing Wang Chen Cao Chun Zhu Zhengwei Li Zhenbang Nie Shuonan Wang Han Yin 《Journal of Rock Mechanics and Geotechnical Engineering》 SCIE CSCD 2024年第6期2154-2171,共18页
Natural slopes usually display complicated exposed rock surfaces that are characterized by complex and substantial terrain undulation and ubiquitous undesirable phenomena such as vegetation cover and rockfalls.This st... Natural slopes usually display complicated exposed rock surfaces that are characterized by complex and substantial terrain undulation and ubiquitous undesirable phenomena such as vegetation cover and rockfalls.This study presents a systematic outcrop research of fracture pattern variations in a complicated rock slope,and the qualitative and quantitative study of the complex phenomena impact on threedimensional(3D)discrete fracture network(DFN)modeling.As the studies of the outcrop fracture pattern have been so far focused on local variations,thus,we put forward a statistical analysis of global variations.The entire outcrop is partitioned into several subzones,and the subzone-scale variability of fracture geometric properties is analyzed(including the orientation,the density,and the trace length).The results reveal significant variations in fracture characteristics(such as the concentrative degree,the average orientation,the density,and the trace length)among different subzones.Moreover,the density of fracture sets,which is approximately parallel to the slope surface,exhibits a notably higher value compared to other fracture sets across all subzones.To improve the accuracy of the DFN modeling,the effects of three common phenomena resulting from vegetation and rockfalls are qualitatively analyzed and the corresponding quantitative data processing solutions are proposed.Subsequently,the 3D fracture geometric parameters are determined for different areas of the high-steep rock slope in terms of the subzone dimensions.The results show significant variations in the same set of 3D fracture parameters across different regions with density differing by up to tenfold and mean trace length exhibiting differences of 3e4 times.The study results present precise geological structural information,improve modeling accuracy,and provide practical solutions for addressing complex outcrop issues. 展开更多
关键词 Complicated exposed rock surfaces Discontinuity characteristic variation Three-dimensional discrete fracture network modeling Outcrop study Vegetation cover and rockfalls
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F-doped orthorhombic Nb_(2)O_(5) exposed with 97% (100) facet for fast reversible Liþ-Intercalation
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作者 Xiaodi Liu Yufeng Tang +5 位作者 Dan Zhang Guangyin Liu Xinwei Luo Yi Shang Xiu Li Jianmin Ma 《Green Energy & Environment》 SCIE EI CAS CSCD 2024年第4期723-731,共9页
Orthorhombic Nb_(2)O_(5)(T-Nb_(2)O_(5))is attractive for fast-charging Li-ion batteries,but it is still hard to realize rapid charge transfer kinetics for Li-ion storage.Herein,F-doped T-Nb_(2)O_(5) microflowers(F-Nb_(... Orthorhombic Nb_(2)O_(5)(T-Nb_(2)O_(5))is attractive for fast-charging Li-ion batteries,but it is still hard to realize rapid charge transfer kinetics for Li-ion storage.Herein,F-doped T-Nb_(2)O_(5) microflowers(F-Nb_(2)O_(5))are rationally synthesized through topotactic conversion.Specifically,F-Nb_(2)O_(5) are assembled by single-crystal nanoflakes with nearly 97%exposed(100)facet,which maximizes the exposure of the feasible Li^(+)transport pathways along loosely packed 4g atomic layers to the electrolytes,thus effectively enhancing the Li^(+)-intercalation performance.Besides,the band gap of F-Nb_(2)O_(5) is reduced to 2.87 eV due to the doping of F atoms,leading to enhanced electrical conductivity.The synergetic effects between tailored exposed crystal facets,F-doping,and ultrathin building blocks,speed up the Li^(+)/electron transfer kinetics and improve the pseudocapacitive properties of F-Nb_(2)O_(5).Therefore,F-Nb_(2)O_(5) exhibit superior rate capability(210.8 and 164.9 mAh g^(-1) at 1 and 10 C,respectively)and good long-term 10 C cycling performance(132.7 mAh g^(-1) after 1500 cycles). 展开更多
关键词 Exposed facets Orthorhombic Nb_(2)O_(5) F-doping Pseudocapacitive intercalation anode Li-ion storage
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Postoperative encapsulated hemoperitoneum in a patient with gastric stromal tumor treated by exposed endoscopic full-thickness resection: A case report
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作者 Hui-Fei Lu Jing-Jing Li +4 位作者 De-Bin Zhu Li-Qi Mao Li-Fen Xu Jing Yu Lin-Hua Yao 《World Journal of Gastrointestinal Surgery》 SCIE 2024年第2期601-608,共8页
BACKGROUND Gastric stromal tumors,originating from mesenchymal tissues,are one of the most common tumors of the digestive tract.For stromal tumors originating from the muscularis propria,compared with conventional end... BACKGROUND Gastric stromal tumors,originating from mesenchymal tissues,are one of the most common tumors of the digestive tract.For stromal tumors originating from the muscularis propria,compared with conventional endoscopic submucosal dissection(ESD),endoscopic full-thickness resection(EFTR)can remove deep lesions and digestive tract wall tumors completely.However,this technique has major limitations such as perforation,postoperative bleeding,and post-polypectomy syndrome.Herein,we report a case of postoperative serous surface bleeding which formed an encapsulated hemoperitoneum in a patient with gastric stromal tumor that was treated with exposed EFTR.Feasible treatment options to address this complication are described.CASE SUMMARY A 47-year-old male patient had a hemispherical protrusion found during gastric endoscopic ultrasonography,located at the upper gastric curvature adjacent to the stomach fundus,with a smooth surface mucosa and poor mobility.The lesion was 19.3 mm×16.1 mm in size and originated from the fourth ultrasound layer.Computed tomography(CT)revealed no significant evidence of lymph node enlargement or distant metastasis.Using conventional ESD technology for mucosal pre-resection,exposed EFTR was performed to resect the intact tumor in order to achieve a definitive histopathological diagnosis.Based on its morphology and immunohistochemical expression of CD117 and DOG-1,the lesion was proven to be consistent with a gastric stromal tumor.Six days after exposed EFTR,CT showed a large amount of encapsulated fluid and gas accumulation around the stomach.In addition,gastroscopy suggested intracavitary bleeding and abdominal puncture drainage indicated serosal bleeding.Based on these findings,the patient was diagnosed with serosal bleeding resulting in encapsulated abdominal hemorrhage after exposed EFTR for a gastric stromal tumor.The patient received combined treatments,such as hemostasis under gastroscopy,gastrointestinal decompression,and abdominal drainage.All examinations were normal within six months of follow-up.CONCLUSION This patient developed serous surface bleeding in the gastric cavity following exposed EFTR.Serosal bleeding resulting in an encapsulated hemoperitoneum is rare in clinical practice.The combined treatment may replace certain surgical techniques. 展开更多
关键词 Exposed endoscopic full-thickness resection Gastric stromal tumors HEMOPERITONEUM Abdominal infection COMPLICATION Postoperative bleeding Case report
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SnO_2 nano-sheet as an efficient catalyst for CO oxidation 被引量:2
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作者 彭洪根 彭跃 +4 位作者 徐香兰 方修忠 刘玥 蔡建信 王翔 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2015年第11期2004-2010,共7页
Polycrystalline SnO2 fine powder consisting of nano-particles (SnO2-NP), SnO2 nano-sheets (SnO2-NS), and SnO2 containing both nano-rods and nano-particles (SnO2-NR+NP) were prepared and used for CO oxidation. S... Polycrystalline SnO2 fine powder consisting of nano-particles (SnO2-NP), SnO2 nano-sheets (SnO2-NS), and SnO2 containing both nano-rods and nano-particles (SnO2-NR+NP) were prepared and used for CO oxidation. SnO2-NS possesses a mesoporous structure and has a higher surface area, larger pore volume, and more active species than SnO2-NP, and shows improved activity. In contrast, although SnO2-NR+NP has only a slightly higher surface area and pore volume, and slightly more active surface oxygen species than SnO2-NP, it has more exposed active (110) facets, which is the reason for its improved oxidation activity. Water vapor has only a reversible and weak influence on SnO2-NS, therefore it is a potential catalyst for emission control processes. 展开更多
关键词 SnO2 catalyst Nano-sheet Nano-rod Exposed active facet EO oxidation
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英语自学日语考试指导(12)
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作者 刘晓蕖 《语言教育》 2001年第12期25-25,共1页
上期的第二个话题“跳槽”是目前普遍存在的现象,对此人们看法不一。有些人认为这在国外并非什么新鲜事,中国人也开始这样做说明人们的思想解放了.打破了过去那种在一个单位干一辈子的传统观念.这是社会的进步。也有人把“跳槽”看做是... 上期的第二个话题“跳槽”是目前普遍存在的现象,对此人们看法不一。有些人认为这在国外并非什么新鲜事,中国人也开始这样做说明人们的思想解放了.打破了过去那种在一个单位干一辈子的传统观念.这是社会的进步。也有人把“跳槽”看做是人的私欲膨胀,是对金钱和物质利益的过分追求,不利于一个企业或部门的发展,不应提倡。考生如同意后一种观点就可以说:“I don’t think it is reasonable for aperson to change his(her)job frequently.A 展开更多
关键词 think “跳槽” 思想解放 物质利益 考生选择 WAITING ABUSE exposed THROAT SMOKE
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英语自学口语考试指导(13)
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作者 刘晓蕖 《语言教育》 2002年第1期30-30,共1页
“安乐死”是一个很敏感的话题,涉及到方方面面,对此众说不一。到目前为止除个别国家外绝大多数国家都采取谨慎或否定的态度。但是,随着社会的发展,人们的健康水平得到普遍提高, “生命的质量”逐渐成为现代社会人类追求的目标,由此引... “安乐死”是一个很敏感的话题,涉及到方方面面,对此众说不一。到目前为止除个别国家外绝大多数国家都采取谨慎或否定的态度。但是,随着社会的发展,人们的健康水平得到普遍提高, “生命的质量”逐渐成为现代社会人类追求的目标,由此引发大部分专家学者及越来越多的普通百姓对“安乐死”表示肯定。但他们也担心由此而导致的一些有关伦理道德方面的问题。 展开更多
关键词 口语考试 伦理道德方面 大连外国语学院 通讯地址 KILLING SUFFERING ABUSE exposed preserve unnecessary
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水力负荷对Atmosphere-Exposed Biofilm(AEB)净化效果的影响 被引量:2
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作者 王必胜 金明姬 +1 位作者 徐明哲 齐书亭 《西南农业学报》 CSCD 北大核心 2016年第12期2971-2974,共4页
本文采用Atmosphere-Exposed Biofilm(AEB)处理模拟废水,调查分析了水力负荷(4.3、8.5、12.7、17.0、21.3rn/d)对系统处理特性的影响。结果表明,水力负荷对COD、TN、TP具有不同程度的影响,COD、TN、TP最佳去除率分别出现17... 本文采用Atmosphere-Exposed Biofilm(AEB)处理模拟废水,调查分析了水力负荷(4.3、8.5、12.7、17.0、21.3rn/d)对系统处理特性的影响。结果表明,水力负荷对COD、TN、TP具有不同程度的影响,COD、TN、TP最佳去除率分别出现17.0、17.0、21.3m/d。在17.0~21.3m/d负荷范围内,COD、TN出水浓度满足了《城镇污水处理厂污染物排放标准》一级A标准,TP满足一级B标准。在所有运行范围内,系统COD、TN、TP去除速率相对恒定。系统水力负荷与进出水浓度比(C/C0)拟合结果,水力负荷与系统处理特性具有一定相关性。综合水力负荷对系统处理特性的影响,水力负荷为17.0m/d时,Atmosphere.Exposed Biofilm(AEB)系统处理效果较优。 展开更多
关键词 Atmosphere—Exposed BIOFILM 水力负荷 处理特性 去除速率
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句首动词形式考点精练(英文)
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作者 刘新会 《中学英语园地(高三版)》 2006年第12期37-40,共4页
关键词 动词形式 动名词短语 现在分词 exposed think TRUTH LIKELY speakin
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An analytical solution for evaluating the safety of an exposed face in a paste backfill stope incorporating the arching phenomenon 被引量:11
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作者 Xu Zhao Andy Fourie Chong-chong Qi 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2019年第10期1206-1216,共11页
In current underground mining, the stability of the exposed backfill face is a basic issue associated with mining design and has been the subject of considerable research in mining safety and efficiency. In this study... In current underground mining, the stability of the exposed backfill face is a basic issue associated with mining design and has been the subject of considerable research in mining safety and efficiency. In this study, an improved analytical solution for evaluating the safety of vertically exposed faces in backfilling was proposed. Based on a differential slice method, the proposed solution emphasizes the arching effect as having the advantages of more rigor and wider scalability. Feasibility of the proposed solution was validated with classic centrifuge results. Good agreement between compared results indicated that the proposed solution skillfully predicts the behavior of the paste centrifuge model. Additionally, calculation of exposed face safety in sequential filling was presented. The proposed solution has practical significance in mine backfill design. 展开更多
关键词 mine SAFETY cemented PASTE BACKFILL EXPOSED FACE ARCHING sequential filling
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Ultimately exposed roof area prediction of bauxite deposit goaf based on macro joint damage 被引量:12
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作者 Lichun Jiang Chao Yang Huazhe Jiao 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2020年第5期699-704,共6页
The ultimately exposed roof area(UERA)of goaf is crucial to the safety and economics of underground mining.The prediction models do not consider the mechanical weakness of rock mass and ignore the influence of the joi... The ultimately exposed roof area(UERA)of goaf is crucial to the safety and economics of underground mining.The prediction models do not consider the mechanical weakness of rock mass and ignore the influence of the joint damage factor,causing a large predicted exposure area with a high roof falling risk.This work adopted joint damage factor to derive a new UERA prediction model.The relationships between the UERA(S)and the span ratio(m),the density(k)and the diameter of fracture(d)were analysed by the new prediction model.The results showed that the exposed area S and the span ratio m have a U-shaped curve relationship.The S decreases with the increase of m and then increases when m is beyond 2.The exposed roof area S is in an inversely proportional power-law relationship with the fracture surface density k,and the curvature of the S-k relationship curve decreases when d=0.5 and k>7,and S is close to 0.There is a negative correlation between S and the fracture surface diameter d,the curvature of the S-d curve decreases with the increase of d and k,and the variation rate increases first and then decreases with the increase of d;when k=0.5 and d>9,S is close to 0.The predicted values of the UERA prediction model are 119.3,112.8,and 114.6 m2 with different joint damage parameters,which are slightly smaller than the actual critical exposure area of a roof(S=120 m2).The case study shows that the alternative prediction model is reasonable and acceptable and provides new theoretical support for the underground mining safety of sedimentary bauxite ore. 展开更多
关键词 Ultimately exposed roof area Bauxite goaf Prediction model Macro joint damage
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Lymphocyte Subsets and Sister-chromatid Exchanges in the Students Exposed to Formaldehyde Vapor 被引量:15
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作者 YING CHEN-JIANG YE XIAO-LEI +6 位作者 XIE HONG YAN WEN-SHENG ZHAO MEI-YING XIA TONG AND YIN SHU-YI.(Department of Environmental Health, Tongji Medical University, Wuhan 430030, China Department of Public Health, Wenzhou Medical College, Wenzhou 317400, China Department of Anatomy,Tongji Medical University, Wuhan 430030, China) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1999年第2期88-94,共7页
The present report evaluates the effects of formaldehyde (FA) exposure on peripheral lymphocytes by using heth genetic and immunological parameters. Twenty-three non-smoking students in the study had inhalation exposu... The present report evaluates the effects of formaldehyde (FA) exposure on peripheral lymphocytes by using heth genetic and immunological parameters. Twenty-three non-smoking students in the study had inhalation exposure to 0.508 ±0. 299 mg/m3 of FA for a Period of 8 weeks (3h × 3 times each week) during anatomy classes. As for composition of lymphocyte subsets after FA exposare,significant increase was found in the percentage of CD19(B cells), while sighficant decrease was observed in CD3(total T cells), CD4(T helper-inducer cells), and CD8(T cytotoxic-suppressior cells) with a P<0 .01. Increase in the ratio of T-helper-inducer cells to T-cytotoxic-suppressor cells (T4 / T8) was also observed with statistical sighcance after exposure (P < 0.001). In the meanwhile,no significant difference (P > 0 .05) was reported between lymphocyte prolifendion rate and sisterchromatid exchange (SCE) at the exposure level and duration. It is suggested that the lymphocyte subsets may be most susceptible to the effects of FA, though a single immunological endpoint is rarely related with pathophysiological interpretation. 展开更多
关键词 RES FA DNA Lymphocyte Subsets and Sister-chromatid Exchanges in the Students Exposed to Formaldehyde Vapor HECK
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Sedimentary Facies and Distribution of Reservoir Rocks from the Feixianguan Formation in the Daxian-Xuanhan Region, NE Sichuan 被引量:11
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作者 MA Yongsheng MOU Chuanlong +2 位作者 GUO Xusheng YU Qian TAN Qinyin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2006年第1期137-151,共15页
The Lower Triassic Feixianguan Formation in the Daxian-Xuanhan region, northeastern Sicbuan is interpreted to be a carbonate platform intermediate between the West Hubei-East Cbongqing marine basin and Guangyuan-Wangc... The Lower Triassic Feixianguan Formation in the Daxian-Xuanhan region, northeastern Sicbuan is interpreted to be a carbonate platform intermediate between the West Hubei-East Cbongqing marine basin and Guangyuan-Wangcang marine basin. Outcrops, well logs and seismic data have disclosed that three sedimentary facies can be identified for the formation: open platform, platform exposed shoal and restricted platform facies. During the early stage of deposition of the Feixianguan Formation, there existed a sedimentary framework all the same as the Late Permian one: open platform in the west, and platform exposed shoal, restricted platform and open platform eastwards. The gradual increase of the shoal area permitted eastward migration of the shoal facies. During the deposition of the third member of the Feixianguan Formation, the study area was invaded by temporary transgressions. Till the deposition of the fourth member of the formation, the study area was prevailed over the unified restricted platform deposits, as indicated by the sedimentary model for the typical carbonate platform shoal deposits. The reservoir rocks in the Feixianguan Formation consist mostly of solution opening dolostone, and the rock types are assembled by oolitic dolostone, residual oolitic dolostone and sucrosic residual oolitic medium- to coarse-grained dolostone. The deep and shallow dual laterologs show relatively high resistivity, clear amplitude differences and time difference saltation of acoustic waves in some intervals. The seismic responses are indicated by low-frequency and highly variable amplitudes and chaotic reflection configurations. The reservoir rocks are characterized by high porosity-high permeability and medium porosity-medium permeability, showing a marked correlation between porosity and permeability. Solution openings are extremely developed in the reservoir rocks, including cast pores, intergranular solution openings, intercrystal pores, intercrystal solution openings, solution openings (caves) and minute fissures. Macropores and coarse pore throats are common. The reservoir rocks are apparently controlled by sedimentary facies in distribution patterns. Vertically, they occur dominantly in the second and first members of the Feixianguan Formation, and laterally in the platform exposed shoals and restricted platforms, where good natural gas potential is expected. 展开更多
关键词 Daxian-Xuanhan region Feixianguan Formation carbonate platform exposed shoal physical property distribution of reservoir rocks
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Damage analysis of POZD coated square reinforced concrete slab under contact blast 被引量:5
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作者 Wei Wang Qing Huo +3 位作者 Jian-chao Yang Jian-hui Wang Xing Wang Wei-liang Gao 《Defence Technology(防务技术)》 SCIE EI CAS CSCD 2022年第9期1715-1726,共12页
High efficiency, environmental protection and sustainability have become the main theme of the development of the protection engineering, requiring that the components not only meet the basic functions, but also have ... High efficiency, environmental protection and sustainability have become the main theme of the development of the protection engineering, requiring that the components not only meet the basic functions, but also have chemical properties such as acid and alkali corrosion resistance and aging resistance. Polyisocyanate-oxazodone(POZD) polymer has the above characteristics, it also has the advantages of strong toughness, high strength and high elongation. The concrete slab sprayed with POZD material has excellent anti-blast performance. In order to explore the damage characteristics of POZD sprayed concrete slabs under the action of contact explosion thoroughly, the contact explosion test of POZD concrete slabs with different charges were carried out. On the basis of experimental verification,numerical simulation were used to study the influence of the thickness of the POZD on the blast resistance of the concrete slab. According to the test and numerical simulation results that as the thickness of the coating increases, the anti-blast performance of the concrete slab gradually increases,and the TNT equivalent required for critical failure is larger. Based on the above analysis, empirical expressions on normalized crater diameter, the normalized spall diameter and normalized spall diameter are obtained. 展开更多
关键词 Contact exposion Square reinforced concrete slab POZD coating Numerical simulation
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Treating aplasia cutis congenita in a newborn with the combination of ionic silver dressing and moist exposed burn ointment: A case report 被引量:4
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作者 Guo-Feng Lei Jun-Ping Zhang +6 位作者 Xiao-Bing Wang Xiao-Li You Jin-Ya Gao Xiao-Mei Li Mei-Ling Chen Xiu-Qin Ning Jiang-Li Sun 《World Journal of Clinical Cases》 SCIE 2019年第17期2611-2616,共6页
BACKGROUND Aplasia cutis congenita (ACC) in newborns is a condition in which congenital defects or hypoplasia is present in part of the epidermis,dermis and even subcutaneous tissue (including muscle and bones).First ... BACKGROUND Aplasia cutis congenita (ACC) in newborns is a condition in which congenital defects or hypoplasia is present in part of the epidermis,dermis and even subcutaneous tissue (including muscle and bones).First reported by Cordon in 1767,ACC is a rare disease with a low incidence of 1/100000 to 3/10000.Currently,there are 500 cases reported worldwide.ACC can be accompanied by other malformations.The onset mechanism of the disease remains unknown but is thought to be correlated to factors such as genetics,narrow uterus,foetal skin and amniotic membrane adhesion,use of teratogenic drugs in early pregnancy and viral infection.CASE SUMMARY In August 2018,we treated a newborn with ACC on the left lower limbs using a combination of ionic silver dressing and moist exposed burn ointment (MEBO) and achieved a satisfactory treatment outcome.The skin defects were observed on the external genitals and on areas from the left foot to 3/4 of the upper left side.Subcutaneous tissue and blood vessels were observed in the regions with skin defects.The following treatments were provided.First,the wound was rinsed with 0.9% sodium chloride solution followed by disinfection with povidone-iodine twice.And then MEBO was applied to the wound at a thickness of approximately 1 mm.After applying ionic silver dressing,the wound was covered with sterile gauze.The wound dressing was replaced every 2-3 d.At the 4-mo follow-up,the treatment outcome was satisfactory.There was minimal scar tissue formation,and limb function was not impaired.CONCLUSION The combination of ionic silver dressing and MEBO to ACC is helpful. 展开更多
关键词 APLASIA cutis congenita Newborns IONIC SILVER DRESSING Moist EXPOSED burn OINTMENT
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In-situ decoration of metallic Bi on BiOBr with exposed(110)facets and surface oxygen vacancy for enhanced solar light photocatalytic degradation of gaseous n-hexane 被引量:6
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作者 Qingqing Yu Jiangyao Chen +4 位作者 Yanxu Li Meicheng Wen Hongli Liua Guiying Li Taicheng An 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2020年第10期1603-1612,共10页
Photocatalytic degradation of gaseous pollutants on Bi-based semiconductors under solar lightirradiation has attracted significant attention.However,their application in gaseous straight-chainalkane purification is st... Photocatalytic degradation of gaseous pollutants on Bi-based semiconductors under solar lightirradiation has attracted significant attention.However,their application in gaseous straight-chainalkane purification is still rare.Here,a series of Bi/BiOBr composites were solvothermally synthe-sized and applied in solar-light-driven photocatalytic degradation of gaseous n-hexane.The charac-terization results revealed that both increasing number of functional groups of alcohol solvent(from methanol and ethylene glycol to glycerol)and solvothermal temperature(from 160 and 180to 200℃)facilitated the in-situ formation of metallic Bi nanospheres on BiOBr nanoplates withexposed(110)facets.Meanwhile,chemical bonding between Bi and BiOBr was observed on theseexposed facets that resulted in the formation of surface oxygen vacancy.Furthermore,the synergis-tic effect of optimum surface oxygen vacancy on exposed(110)facets led to a high visible light re-sponse,narrow band gap,great photocurrent,low recombination rate of the charge carriers,andstrong·O2-and h*formation,all of which resulted in the highest removal efficiency of 97.4%within120 min of 15 ppmv of n-hexane on Bi/BiOBr.Our findings efficiently broaden the application ofBi-based photocatalysis technology in the purification of gaseous straight-chain pollutants emittedby the petrochemical industry. 展开更多
关键词 Bi/BiOBr composite Exposed(110〕facet surface oxygen vacancy Solar light photocatalysis Degradation of gaseous alkane
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Micronuclei in Nasal Mucosa, Oral Mucosa and Lymphocytes in Students Exposed to Formaldehyde Vapor in Anatomy Class 被引量:7
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作者 YING CHEN -JlANG YAN WEN-SHENG +4 位作者 ZHAO MEI-YING YE XIAO-LEI XIE HONG YIN SHU-YI ZHU XIAN-SHU(Department of Environmental Health, n Dgurtment of Anatomy,Tongji the ical University, Wuhan, China)(Department of Public Health, Wengzhou theical Chllege, Ch 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1997年第4期451-455,共5页
The frequency of micronuclei (MN) in cells of the nasal mucosa, oral mucosa and in lym-phocytes was evaluated for 25 students in anatomy classes exposed to formaldehyde (FA) overan 8-week period. Each student served a... The frequency of micronuclei (MN) in cells of the nasal mucosa, oral mucosa and in lym-phocytes was evaluated for 25 students in anatomy classes exposed to formaldehyde (FA) overan 8-week period. Each student served as his or her own control. The time-weighted averageconcentration (TWA) of fOrmaldehyde in anatomical laboratories and in students' dormitorieswas 0. 508 ± 0. 299 mg/m3 and 0. 012 ± 0. 0025mg/m3, respectively. A higher frequency ofmicronuclei was observed in nasal and oral exfoliative cells after formaldehyde exposure (3. 85± 1. 48 vs 1 .20± 0. 676 and 0. 857 ± 0. 558 vs 0. 568 ± 0. 317, paired-t test: P< 0. 001and P < 0. 01, respectively). No significant increase in the frequency of lymphocyte micronu-clei was found after formaldehyde exposure (P >0. 05 ). The present study shows that nasalmucosa cel1s exposed through respiration are the chief target of FA-induced genotoxic effects 展开更多
关键词 Res Oral Mucosa and Lymphocytes in Students Exposed to Formaldehyde Vapor in Anatomy Class Micronuclei in Nasal Mucosa NIOSH
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DESERTIZATION OF THE CONTINENTAL SHELF OF CHINA IN THE LATER STAGE OF LATE PLEISTOCENE 被引量:2
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作者 赵松龄 李国刚 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1990年第4期289-298,共10页
In the later stage of Late Pleistocene, global climate entered into the climax period of Wurm when temperature decreased remarkably and glaciers developed. Information from the East China Sea also confirm that the sea... In the later stage of Late Pleistocene, global climate entered into the climax period of Wurm when temperature decreased remarkably and glaciers developed. Information from the East China Sea also confirm that the sea level fell by at least 130 m at that time (Emery, 1968). The Bohai Sea and Yellow Sea at the climax period were totally exposed, while the East China Sea and South China Sea shelf regions were exposed partly. The exposed shelf area exceeded 1 million km2 and became a salty desert where land plants could not survive. Such were the conditions which led to the desertization of the shelf region.Eolation was the major exogenetic force not only on land but also on the shelf region in the ice age. At the climax period of Wiirm, the northern part of China developed thick layers of loess deposits. The shelf region at that time had similar climatic conditions and sediments. Because the shelf region was not protected by vegetation in the ice age, intensive wind storms remoulded the primarily 展开更多
关键词 SHELF PLEISTOCENE vegetation exposed DESERT Bohai CLIMATIC LOESS Yellow thick
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Oxygen migration triggering molybdenum exposure in oxygen vacancy-rich ultra-thin Bi_(2)MoO_(6) nanoflakes: Dual binding sites governing selective CO_(2) reduction into liquid hydrocarbons 被引量:5
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作者 Weili Dai Jianfei Long +5 位作者 Lixia Yang Shuqu Zhang Yong Xu Xubiao Luo Jianping Zou Shenglian Luo 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2021年第10期281-289,I0009,共10页
Oxygen vacancy plays vital roles in regulating the electronic and charge distribution of the oxygen deficient materials.Herein,abundant oxygen vacancies are created during assembling the two-dimensional(2D)ultra-thin ... Oxygen vacancy plays vital roles in regulating the electronic and charge distribution of the oxygen deficient materials.Herein,abundant oxygen vacancies are created during assembling the two-dimensional(2D)ultra-thin Bi_(2)MoO_(6) nanoflakes into three dimensional(3D)Bi_(2)MoO_(6) nanospheres,resulting in significantly improved performance for photocatalytical conversion of CO_(2) into liquid hydrocarbons.The increased performance is contributed by two primary sites,namely the abundant oxygen vacancy and the exposed molybdenum(Mo)atom induced by oxygen-migration,as revealed by the theoretical calculation.The oxygen vacancy(Ov)and uncovered Mo atom serving as dual binding sites for trapping CO_(2) molecules render the synchronous fixation-reduction process,resulting in the decline of activation energy for CO_(2) reduction from 2.15 eV on bulk Bi_(2)MoO_(6) to 1.42 eV on Ov-rich Bi_(2)MoO_(6).Such a striking decrease in the activation energy induces the efficient selective generation of liquid hydrocarbons,especially the methanol(C_(2)H_(5) OH)and ethanol(CH_(3) OH).The yields of CH_(3) OH and C_(2)H_(5) OH over the optimal Ov-Bi_(2)MoO_(6) is high up to 106.5 and 10.3μmol g^(-1) respectively,greatly outperforming that on the Bulk-Bi_(2)MoO_(6). 展开更多
关键词 CO_(2)photoreduction Ultra-thin Bi_(2)MoO_(6)nanoflake Oxygen vacancy Exposed Mo atom Oxygen migration
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Detection of Cytogenetic Effects in Peripheral Lymphocytes of Students Exposed to Formaldehyde with Cytokinesis-Blocked Micronucleus Assay 被引量:7
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作者 HEJI-LIANG JINLI-FEN 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1998年第1期87-92,共6页
Cytokinesis-blocked micronucleus assay was applied as a biological dosimeter to detect abnormalities in human peripheral lymphocytes of thirteen students exposed to formaldehyde (FA) during a 12-week (10 h per week) a... Cytokinesis-blocked micronucleus assay was applied as a biological dosimeter to detect abnormalities in human peripheral lymphocytes of thirteen students exposed to formaldehyde (FA) during a 12-week (10 h per week) anatomy class. Breathing-zone air samples colleeted during dissection procedures showed a mean concentration of 2. 37 ppm (3. 17mg/m3 ). Ten students from the same school but without FA exposure served as controls. Chromosome aberrations (CA) and sister chromatid exchanges (SCE) were detected in both groups. The micronuclei (MN) rate (6. 38 ± 2. 50‰ ) and CA rate (5. 92 ±2. 40‰ ) in the FA-exposed group showed a significant increase (P< 0. 01 ) when compared with those of the controls (3. 15 ±1. 46‰and 3. 40 ± 1. 57 % respectively). A correlation between MN and CA in individuals was observed. SCE in the exmpd group were also increased (P< 0. 05), but not so greatly as MN or CA. The results indicated that FA might damage the chromosomes of human lymphocytes. 展开更多
关键词 Res Detection of Cytogenetic Effects in Peripheral Lymphocytes of Students Exposed to Formaldehyde with Cytokinesis-Blocked Micronucleus Assay
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Long-term medical treatment of patients with severe burns at exposed sites 被引量:3
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作者 Yong Du Guo-Zhong Lv +2 位作者 Shun Yu Dan Wang Qian Tan 《World Journal of Clinical Cases》 SCIE 2020年第16期3515-3526,共12页
BACKGROUND Body parts such as the face and hands are highly exposed during daily life and burns may accumulate in these areas.In addition,residual wounds,scar hyperplasia and contracture often exist in the late stage ... BACKGROUND Body parts such as the face and hands are highly exposed during daily life and burns may accumulate in these areas.In addition,residual wounds,scar hyperplasia and contracture often exist in the late stage of a deep burn in these areas,which may affect patients’appearance,movements,and mental health.However,inadequate attention has been paid to this issue which can result in problems,such as difficulty in healing,possibility of carcinoma,chronic pain and a heavy mental burden.AIM To investigate the long-term medical treatment of patients with severe burns at exposed sites following a mass burn casualty event.METHODS A retrospective analysis of 13 patients with severe burns at exposed sites was performed to determine their respective long-term medical treatment.A combined wound dressing scheme consisting of traditional Chinese and Western medicine was introduced to repair residual wounds.Active and passive functional exercises with massage,Chinese herbal baths and compression fixation were proposed to ameliorate the condition of the hands.A combination of physical,chemical and photoelectrical measures was adopted for anti-scar treatment.A psychological intervention and recovery guide was provided which corresponded to the patients’psychological status.RESULTS Compared to patients who did not simultaneously receive the same treatment,patients who underwent systematic treatment recovered with a lower woundinfection rate(P<0.05),a shorter healing time(13.6±3.2 d)compared with(19.1±3.5 d)and more bearable pain during wound dressing at three days,one week and two weeks after a Chinese herbal bath(P<0.05).Satisfactory results were achieved with regard to restored function of patients’joints and blood supply to nerve endings,closure of the eyelids and the size of mouth opening tended to be normal,and only 7.1%of patients were diagnosed with severe scar hyperplasia and contracture deformity compared with 30.7%in the control group.In addition,the color,thickness,vascular distribution and softness score of the scars improved(P<0.01),and the effects of the psychological intervention was remarkable as shown by the Self-Rating Anxiety Scale and Self-Rating Depression Scale.CONCLUSION A better prognosis can be achieved in patients in the late stage of a burn with active residual wound repair,limb functional exercise,anti-scar and psychological rehabilitation. 展开更多
关键词 Exposed sites Severely burned patients Mass burn casualty Medical treatment
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