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Additive Maps Preserving the Truncation of Operators

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Journal of Mathematical Research with Applications 2022年第1期42卷 89-94页

作者： jie yao Guoxing JI School of Mathematics and Statistics Shaanxi Normal University

Let H be a complex Hilbert space and B（H） the algebra of all bounded linear operators on H. An operator A is called the truncation of B in B（H） if A = PABPA*, where PA and PA*denote projections onto the closures of R（A） and R（A*）, respectively. In this paper,we determine the structures of all additive surjective maps on B（H） preserving the truncation of operators in both directions.

关键词： truncation of operator operator equation additive map preserver

Carbamate Synthesis from Aromatic Amines and Dimethyl Carbonate Using Lead Acetate as Catalyst

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Chemical Research in Chinese Universities 2006年第5期22卷 669-670页

作者： KANG Wu-kui WANG Gong-ying yao jie Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 P. R. China Graduate School of Chinese Academy of Sciences Beijing 100039 P. R. China

Carbamates are important intermediates in the syntheses of pesticides, herbicides, drugs, polyurethane-based polymers, and other fine and commodity chemicals.

关键词： Carbamate Amine Dimethyl carbonate Lead acetate

Investigating the effect of the Tibetan Plateau on the ITCZ using a coupled Earth system model

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Atmospheric and Oceanic Science Letters 2023年第1期16卷 53-58页

作者： Chuqiao Yan jie yao Xingchen Shen Haijun Yang Department of Atmospheric and Oceanic Sciences and CMA-FDU Joint Laboratory of Marine Meteorology Fudan UniversityShanghaiChina Shanghai Scientific Frontier Base for Ocean-Atmosphere Interaction Studies Fudan UniversityShanghaiChina Department of Atmospheric and Oceanic Sciences School of PhysicsPeking UniversityBeijingChina Science&Technology on Integrated Information System Laboratory Institute of SoftwareChinese Academy of SciencesBeijingChina

本文利用耦合地球气候系统模式研究了青藏高原对热带辐合带(ITCZ)的影响.我们研究发现热带大西洋ITCZ的位置对青藏高原存在与否有明显的敏感性.与目前真实情况相比,移除青藏高原会导致北半球海面降温,南半球海面升温.这种海面温度变化... 详细信息

本文利用耦合地球气候系统模式研究了青藏高原对热带辐合带(ITCZ)的影响.我们研究发现热带大西洋ITCZ的位置对青藏高原存在与否有明显的敏感性.与目前真实情况相比,移除青藏高原会导致北半球海面降温,南半球海面升温.这种海面温度变化在大西洋表现得尤为明显,导致热带大西洋最大海温中心向南移动,从而迫使大气对流中心向南移动,即表现为ITCZ的南移.相应地,夏季热带大气Hadley环流的上升支也发生明显南移.北(南)半球海洋变冷(变暖)这种态势要求增强跨赤道向北的大气经向热量输送,从而维持各个半球的能量平衡,而这需要ITCZ位置的南移才能实现.本文研究表明,青藏高原的存在在现今ITCZ气候态的形成中可能扮演了重要角色.

关键词：青藏高原热带辐合带耦合地球气候模式 Hadley环流热量输送

Transesterification of Ethylene Carbonate with Dimethyl Terephthalate over Various Metal Acetate Catalysts

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Chemical Research in Chinese Universities 2007年第2期23卷 173-175页

作者： ZHANG Dan JIA Shu-yong WANG Yue yao jie WANG Gong-ying Chengdu Institute of Organic Chemistry Chinese Academy of Sciences Chengdu 610041 P. R. China Graduate School of Chinese Academy of Sciences Beijing 100039 P. R. China

The reaction between ethylene carbonate and dimethyl terephthalate was carried out for the simultaneous synthesis of dimethyl carbonate and poly（ethylene terephthalate）, This reaction is an excellent chemical process that is environmentally friendly and produces no poisonous substance. The metal acetate catalysts used for this reaction are discussed in detail. Lithium acetate dihydrate was found to be a novel and efficient catalyst for this reaction. Compared with other metal acetates, lithium acetate dihydrate can attain a maximum catalytic activity at a lower concentration. When the reaction was carried out under the following conditions： the reaction temperature from 230 to 250 ℃, molar ratio of ethylene carbonate（EC） to dimethyl terephthalate（DMT） 3： 1, reaction time 3 h, and a catalyst amount of 0. 4% （molar fraction to DMT）, the yield of dimethyl carbonate（DMC） was 79. 1%.

关键词： Metal acetate Ethylene carbonate Dimethyl terephthalate Dimethyl carbonate Poly( ethylene terephthalate )

Influence of intensification pressures on pores in die-cast ADC12 alloys

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China Foundry 2019年第3期16卷 184-189页

作者： Chun-tao Wang jie yao Hai-dong Zhao Run-sheng Yang Ningbo Heli Mould Technology Co. Ltd. Industrial Park Xiangshan County Ningbo 315700 China National Engineering Research Center of Near-net Shape Forming for Metallic Materials South China University of Technology Guangzhou 510641 China

Die casting process is widely applied in making Al parts. However, due to high speed of liquid metal flow in the die cavity, gases are prone to be entrapped in the filling, resulting in porosity defects. The X-ray computed tomography scanning technique was used to detect the pores in die-cast ADC12 alloys with different intensification pressures. The three-dimensional features of pores including pore size, number, sphericity have been obtained. The effect of different intensification pressures on two different kinds of pores, namely gas-pores and shrinkage pores, was analyzed. The results show that with increasing the pressure, the pore fractions and quantity gradually decrease. When the pressure increased to 85 MPa, the pores from gas entrapment during the mold filling were compressed, leading to a lower porosity fraction. The pressure cannot affect the pores in the samples with a thin wall (2 mm) due to a great solidification rate.

关键词： die casting intensification pressure porosity X-ray computed tomography

Tunable double-resonance dimer structure for surface-enhanced Raman scattering substrate in near-infrared region

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Photonics Research 2015年第6期3卷 313-316页

作者： Zhengqing Qi jie yao Liangliang Zhao Yiping Cui Changgui Lu Advanced Photonics Center Southeast UniversityNanjing 210096China Nanjing Normal University Nanjing 210023China

Plasmonic resonance with Fano lineshape has attracted a great deal of recent interest. Here we design a new structure with a dimer grating upon a gold film separated by a layer of silica spacer, which has two resonant modes corresponding to the dimer’s localized surface plasmon resonance and the surface plasmon resonance excited by the dimer grating. This structure has three advantages for near-infrared detection in water. First, it provides two resonant modes to enhance the excitation and scattered signals of surface-enhanced Raman ***, coupling of these two modes results in a Fano resonance, providing a higher electric field ***, the dimer provides more flexible tunability compared to a single disk structure.

关键词： LSPR mode SERS

Efficacy of microcatheter-assisted trabeculotomy on secondary glaucoma after congenital cataract surgery

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International Journal of Ophthalmology(English edition) 2022年第10期15卷 1604-1610页

作者： Wen-Jing Zhang Ying Qi Xue-Tao Huang Ren-jie yao Department of Ophthalmology the First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450052Henan ProvinceChina

AIM: To evaluate efficacy of microcatheter-assisted trabeculotomy(MAT) in eyes with secondary glaucoma after congenital cataract surgery and explore its correlation with the different degree of trabeculotomy. METHODS: A retrospective analysis was conducted on patients who underwent the said procedure between September 2019 and September 2020. The patients were classified into two groups according to the degree of trabeculotomy(group 1: ≤240-degree;group 2: 240–360-degree). The intraocular pressure(IOP) and antiglaucoma drugs before and after operation was collected during the 12-month follow-up. RESULTS: Totally 27 eyes of 25 patients were included: 11(40.7%) eyes in group 1 and 16(59.3%) eyes in group 2. The mean IOP of all patients was 34.67±9.18 mm Hg preoperatively and 8.74±4.32, 9.95±5.65, 14.39±5.30, 16.02±4.37, 15.82±3.28, and 16.19±3.56 mm Hg 1 d, 1 wk, 1, 3, 6, and 12 mo after surgery, respectively. In all patients, there were significant differences in IOP at each time point(F=65.614, P0.05). At the end of follow-up, the partial success rate was 81.8% in group 1 vs 93.75% in group 2(P=0.549). Various amount of intraoperative and postoperative hyphema occurred in all eyes, which spontaneously absorbed or cleaned through paracentesis and irrigation. No other serious complications was ***: MAT can effectively reduce IOP in patients with secondary glaucoma after congenital cataract surgery with a high success rate and safety. And it can be used as the first choice for the treatment of secondary glaucoma after surgery for congenital cataracts.

关键词： secondary glaucoma congenital cataract microcatheter-assisted trabeculotomy illuminated microcatheter intraocular pressure

Omental mass combined with indirect inguinal hernia leads to a scrotal mass: A case report

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World Journal of Clinical Cases 2021年第26期9卷 7850-7856页

作者： Jia-Yi Liu Shuai-Qi Li Shi-jie yao Qian Liu Department of Urology Tianjin First Central HospitalSchool of MedicineNankai UniversityTianjin 300192China School of Medicine Nankai UniversityTianjin 300192China

BACKGROUND Primary omental tumors are uncommon,and omental fibromas account for 2%of these *** to the low incidence of omental fibromas and the limited relevant literature,it is challenging for clinicians to make an accurate diagnosis of this condition,especially before *** SUMMARY A 30-year-old man was admitted to the hospital because of a left epididymal mass with vague discomfort for more than 1 mo.A physical examination was performed,and the findings showed that the epididymal mass may have entered the abdominal *** computed tomography was performed in our hospital and revealed a left inguinal hernia with a mass in the hernial contents,and no masses were found in the left epididymis.A traditional inguinal hernia incision was *** hernia contents were found to be of the greater omentum,and a 2.5 cm-diameter mass was found at the distal end of the greater *** scrotum and epididymis did not exhibit other ***,the mass of the greater omentum was *** frozen pathological examination suggested a spindle cell *** postoperative pathological examination suggested that the mass was an omental ***,the patient recovered well and was *** re-examinations were performed at 1 mo and half a year after the operation and showed no obvious *** Due to the low morbidity rate associated with and latent nature of omental tumors,these tumors are difficult to diagnose preoperatively;thorough medical history taking,detailed physical examinations,and necessary imaging auxiliary examinations can help clinicians diagnose and treat these cases.

关键词： Diagnosis Epididymal mass Omental mass Inguinal hernia Angiofibroma Case report

Soft substrate and decreased cytoskeleton contractility promote coupling and morphology maintenance of pluripotent stem cells

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Acta Mechanica Sinica 2021年第10期37卷 1520-1529,I0002页

作者： Meihong Lu Jialing Cao Yuanyuan Zhai Peng Zhao jie yao Yan Gong Jing Du Yubo Fan Key Laboratory for Biomechanics and Mechanobiology of the Ministry of Education Institute of Nanotechnology for Single Cell AnalysisBeijing Advanced Innovation Center for Biomedical EngineeringSchool of Biological Science and Medical EngineeringBeihang UniversityBeijing100083China Institute of Biomechanics and Medical Engineering Department of Mechanical EngineeringSchool of AerospaceTsinghua UniversityBeijing100084China Sino-French Engineer School Beihang UniversityBeijing100083China School of Material Science&Engineering Beijing Institute of Fashion TechnologyBeijing100029China

The mechanical microenvironment affects the morphology and mechanical properties of cells, and it also plays an important role in cell functions. Pluripotent stem cells (PSCs) grow as multicellular colonies, and the coupling effects of cell–cell and cell-extracellular matrix interactions are complex but necessary for the formations and functions of tissues. This paper uses the finite element method to establish a three-dimensional calculation model of a pair of deformed PSCs in contact with each other and considers the growth and depolymerization of actin filaments. Then the effects of substrate stiffness on the morphology of cells and nuclei and the rearrangement of cytoskeleton are demonstrated. As the substrate becomes softer, the nuclei become loose and round, and the actin filaments will be assembled at a lower level, which could promote the formation of compacted cell colony while having a positive effect on maintaining pluripotency and inducing reprogramming efficiency. In addition, stronger activation of cytoskeleton contractility will compress the cytoplasm and nuclei. The cell mechanics model proposed in this paper provides a strategy for studying the cell morphology and cytoskeleton response of the two-cell system under different biophysical stimuli, and also lays the foundation for the further research on more mechanical factors of cell pluripotency.

关键词： Pluripotent stem cells Morphology Cell model Mechanical stimuli