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Oxidizing mechanism of podophyllotoxin and its derivatives by sodium persulfate

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Science China Chemistry 1996年第4期39卷 425-432页

作者：汪世龙姚思德张志成张曼维姜岳 Department of Applied Chemistry University of Science and Technology of China Hefei 230026 China Laboratory of radiation Chemistry Shanghai Institute of Nuclear Research Chinese Academy of Sciences Shanghai 201800 China.

The oxidizing mechanism of podophyllotoxin and its derivatives by sodium persulfate has been studied by laser flash photolysis and pulse radiolysis. The formation and decay processes of transient species of podophyllotoxin and its derivatives have been observed, and a series of rate constants for the formation and decay of transient species have been determined. It has been found that there is a light (UV) sensitive group on the C-4 of podophyllotoxin and two light (UV) sensitive groups on the C-4 and C-4’ of 4’-demethylepipodophyllotoxin.

关键词： podophyllotoxin laser flash photolysis pulse radiolysis sodium persulfate.

Integrity-Management Characteristics and Efficiency Evaluation of Oil and Gas Pipelines

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China Petroleum Processing & Petrochemical Technology 2023年第4期25卷 139-150页

作者： Zhang Xiaodong Sun Jiazheng Fu Yong Lei Shaojuan School of Economics and Management University of Science and Technology BeijingBeijing 100083China PetroChina Planning and Engineering institute Beijing 100083 China Nuclear and radiation Safety Center Beijing 102444China

Pipeline integrity is a cornerstone of the operation of many industrial systems, and maintaining pipeline integrity is essential for preventing economic losses and ecological damage caused by oil and gas leaks. Based on integritymanagement data published by the US Pipeline and Hazardous Materials Safety Administration, this study applied the k-means clustering and data envelopment analysis(DEA) methods to both explore the characteristics of pipeline-integrity management and evaluate its efficiency. The k-means clustering algorithm was found to be scientifically valid for classifying pipeline companies as either low-, medium-, or high-difficulty companies according to their integrity-management requirements. Regardless of a pipeline company's classification, equipment failure was found to be the main cause of pipeline failure. In-line inspection corrosion and dent tools were the two most-used tools for pipeline inspection. Among the types of repair, 180-day condition repairs were a key concern for pipeline companies. The results of the DEA analysis indicate that only three out of 34 companies were deemed to be DEA-effective. To improve the effectiveness of pipeline integrity management, we propose targeted directions and scales of improvement for non-DEA-effective companies.

关键词： Integrity management k-means clustering algorithm data envelopment analysis safety management

Preparation of pH-sensitive poly（ethylene oxide） hydrogels grafted by gamma-ray irradiation and their applications for drug delivery system

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Preparation of pH-sensitive poly（ethylene oxide） hydrogels...

Preparation and characterization of FPGX hydrogel dosimeters

The 1st Asian-Pacific Symposium on radiation Chemistry

作者： Young-Chang NHO Youn-Mook LIM Il-Hiun KUK radiation Application Research Division Advanced Radiation Technology Institute Korea radiation Application Research Division Advanced Radiation Technology Institute Korea radiation Application Research Division Advanced Radiation Technology Institute Korea

Hydrogels are three-dimensional networks of hydrophilic polymers held together by crosslinks of covalent bonds or ionic bonds and secondary forces in the form of hydrogen bonds or hydrophobic interactions [1, 2]. Environmentally sensitive hydrogels have an enormous potential for various applications. Either pH-sensitive and/or temperature- sensitive hydrogels can be used for a site-specific controlled drug delivery [3]. Especially, pH-sensitive hydrogels have been most frequently used to develop controlled release formulations for oral administration [3, 4]. All the pH-sensitive hydrogels contain pendent acidic, for example carboxylic and sulfonic acids, or basic, for example ammonium salts, groups that either accept or release protons in response to changes in environmental pH[3-5]. These ionic hydrogels are the swollen polymer networks which show sudden or gradual changes in their dynamic and equilibrium swelling behavior as a result of changing the external pH. In these gels, ionization occurs when the pH of the environment is above the pKa of the ionizable group [5]. As the degree of ionization increases （pH increase in the system）, the number of fixed charges increases, resulting in increased electrostatic repulsions between the chains [4].

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Nuclear Science and Techniques 2010年第1期21卷 60-62页

作者： Xiao Ruijia Yang Liming Chen Jie Qian Qiang Rong Liang Cao Fangqi Luo Wenyun Dong Xiaoqing Zha Yuanzi Wu Guohua School of Environmental and Chemical Engineering Shanghai University Shanghai 200444 China Department of radiation Oncology Xin Hua Hospital Affiliated to Shanghai Jiao Tong University School of Medicine Shanghai 200092 China

A three dimensional Fricke-(PVA-glutaraldehyde)-xylenol orange (FPGX) hydrogel dosimeter was prepared by chemical crosslinking *** determination was performed by measuring the absorbance change of the dosimeter before and after irradiation using UV-Vis spectrophotometer at 585 *** dose response of the FPGX hydrogel dosimeter related to absorbance change was linear,when it was irradiated by X-ray in the range of 0~2 *** stability of the dosimeter before and after irradiation was evaluated by studying the change of absorbance with time.

关键词：剂量计水凝胶制备紫外可见分光光度计 X射线照射表征化学交联法聚乙烯醇

Integrated strategies for chemotherapy cycles in nasopharyngeal carcinoma patients: Real-world data from two epidemic centers guiding decision-making

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Chinese Journal of Cancer Research 2023年第2期35卷 126-139页

作者： Zejiang Zhan Yingying Huang Jiayu Zhou Zhuochen Cai Haoyang Huang Ying Deng Wenze Qiu Xun Cao Xi Chen Chixiong Liang Lulu Zhang Xiang Guo Taize Yuan Xing Lyu Department of Nasopharyngeal Carcinoma Sun Yat-sen University Cancer Centerthe State Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangdong Key Laboratory of Nasopharyngeal Carcinoma Diagnosis and TherapyGuangzhou 510060China Department of radiation Oncology Affiliated Cancer Hospital and Institute of Guangzhou Medical UniversityGuangzhou 510095China Department of Critical Care medicine Sun Yat-sen University Cancer Centerthe State Key Laboratory of Oncology in South ChinaCollaborative Innovation Center for Cancer MedicineGuangzhou 510060China Department of radiation Oncology Guangzhou Concord Cancer CenterGuangzhou 510045China

objective:Two cycles of induction chemotherapy(IC)followed by 2 cycles of platinum-based concurrent chemoradiotherapy(CCRT)(2IC+2CCRT)for locoregionally advanced nasopharyngeal carcinoma(LA-NPC)is widely adopted but not *** study aimed to determine the clinical value of 2IC+2CCRT regarding efficacy,toxicity and ***:This real-world study from two epidemic centers used propensity score matching(PSM)and inverse probability of treatment weighting(IPTW)*** enrolled patients were divided into three groups based on treatment modality:Group A(2IC+2CCRT),Group B(3IC+2CCRT or 2IC+3CCRT)and Group C(3IC+3CCRT).Long-term survival,acute toxicities and cost-effectiveness were compared among the *** developed a prognostic model dividing the population into high-and low-risk cohorts,and survivals including overall survival(OS),progression-free survival(PFS),distant metastasis-free survival(DMFS)and locoregional relapse-free survival(LRRFS)were compared among the three groups according to certain risk ***:Of 4,042 patients,1,175 were enrolled,with 660,419,and 96 included in Groups A,B and C,***-year survivals were similar among the three groups after PSM and confirmed by *** 3-4 neutropenia and leukocytopenia were significantly higher in Groups C and B than in Group A(52.1%vs.41.5%vs.25.2%;41.7%vs.32.7%vs.25.0%)as were grade 3-4 nausea/vomiting and oral mucositis(29.2%vs.15.0%vs.6.1%;32.3%vs.25.3%vs.18.0%).Cost-effective analysis suggested that 2IC+2CCRT was the least expensive,while the health benefits were similar to those of the other *** exploration showed that 2IC+2CCRT tended to be associated with a shorter PFS in high-risk patients,while 3IC+3CCRT potentially contributed to poor PFS in low-risk individuals,mainly reflected by ***:In LA-NPC patients,2IC+2CCRT was the optimal choice regarding efficacy,toxicity and costeffectiveness;however,2IC+2CCRT and 3IC

关键词： Nasopharyngeal carcinoma treatment modality chemotherapy cycle survival toxicity costeffectiveness real world

Diagnostic use of superb microvascular imaging in evaluating septic arthritis of the manubriosternal joint:A case report

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World Journal of Clinical Cases 2023年第18期11卷 4397-4405页

作者： Goda Seskute Dominyka Kausaite Ana Chalkovskaja Egle Bulotaite Irena Butrimiene Clinic of Rheumatology Orthopaedics Traumatologyand Reconstructive SurgeryCentre of RheumatologyInstitute of Clinical MedicineFaculty of MedicineVilnius UniversityVilnius 01513Lithuania Clinic of Internal Diseases Family Medicine and OncologyInstitute of Clinical MedicineFaculty of MedicineVilnius UniversityVilnius 01513Lithuania Department of Radiology Nuclear Medicine and Medical PhysicsInstitute of Biomedical SciencesFaculty of MedicineVilnius UniversityVilnius 01513Lithuania

BACKGROUND Septic arthritis of the manubriosternal joint is a diagnostic challenge due to its rarity and anatomical *** ultrasound,plain radiographs,and computed tomography are not able to confirm or even suspect arthritis *** microvascular imaging is a new advanced Doppler technique in evaluating low-flow microvascular *** higher sensitivity for increased perisynovial vascularity helps to suspect septic arthritis and forms a methodical approach to using magnetic resonance imaging(MRI).CASE SUMMARY A 34-year-old immunocompetent woman presented with a fever and a dull ache in the chest radiating to the right *** injury and the most common respiratory and cardiac disorders were ruled *** cultures came back positive for Staphylococcus aureus,and sepsis was confirmed.A small lump was noted on the chest during the first week of *** microvascular imaging was performed and septic arthritis of the manubriosternal joint was *** confirmed the diagnosis and showed septic arthritis of the manubriosternal joint with several localized abscesses behind the *** patient was treated for three weeks with intravenous antibiotics and the outcome was favorable:Inflammatory markers became normal,and the lump *** months later,the patient was examined for a new episode of mild pain in the sternum and was diagnosed with persistent perichondritis by ultrasound in comparison with *** Superb microvascular imaging is a useful tool for the early diagnosis of septic arthritis of the manubriosternal joint and following-up.

关键词： Power Doppler Superb microvascular imaging Ultrasound Septic arthritis Manubriosternal joint Case report

Defect types and room-temperature ferromagnetism in undoped rutile TiO_2 single crystals

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Chinese Physics B 2013年第3期22卷 491-494页

作者：李东翔秦秀波郑黎荣李玉晓曹兴忠李卓昕杨静王宝义 Key Laboratory of Nuclear Analysis Techniques Institute of High Energy PhysicsChinese Academy of Sciences School of Physical Engineering Zhengzhou University Research Center for Application of Nuclear Technology Institute of High Energy PhysicsChinese Academy of Sciences Beijing Synchrotron radiation Facility Institute of High Energy PhysicsChinese Academy of Sciences

Room-temperature ferromagnetism has been experimentally observed in annealed rutile TiO2 single crystals when a magnetic field is applied parallel to the sample *** combining X-ray absorption near the edge structure spectrum and positron annihilation lifetime spectroscopy,Ti^3＋-V O defect complexes（or clusters） have been identified in annealed crystals at a high *** elucidate that the unpaired 3d electrons in Ti^3＋ ions provide the observed room-temperature *** addition,excess oxygen ions in the TiO2 lattice could induce a number of Ti vacancies which obviously increase magnetic moments.

关键词： annealing oxygen vacancies Ti^3+-V O defect complexes ferromagnetism

Influence of Cryorolling on the Precipitation of Cu–Ni–Si Alloys: An In Situ X-ray Diffraction Study

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Acta Metallurgica Sinica(English Letters) 2018年第10期31卷 1089-1097页

作者： Wei Wang Zong-Ning Chen En-Yu Guo Hui-Jun Kang Yi Liu Cun-Lei Zou Ren-Geng Li Guo-Mao Yin Tong-Min Wang Key Laboratory of Solidification Control and Digital Preparation Technology (Liaoning Province) School of Materials Science and Engineering Dalian University of Technology Shanghai Synchrotron radiation Facility Shanghai Institute of Applied Physics Chinese Academy of Sciences

The effect of cryorolling on the precipitation process of deformed Cu-Ni-Si alloys was investigated through in situ synchrotron X-ray diffraction technique. The results demonstrate that the precipitation process is significantly accelerated by cryorolling. Cryorolling produces higher dislocation density, which provides more heterogeneous nucleation sites for Ni2Si precipitates, hence promotes precipitation. In the early stage of aging, the enhanced nucleation of precipitates accelerates the depletion of supersaturation, and finer precipitates are obtained. In addition, recrystallization is promoted as a result of high stored energy in the cryorolled Cu-Ni-Si alloys, which facilitates the formation of discontinuous precipitation in the late stage of aging.

关键词： Copper alloy Cryogenic Rolling Aging precipitation Synchrotron radiation X-ray diffraction

Endoscopic ultrasound-guided fiducial marker placement for neoadjuvant chemoradiation therapy for resectable pancreatic cancer

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World Journal of Gastrointestinal Oncology 2020年第7期12卷 768-781页

作者： Reiko Ashida Nobuyasu Fukutake Ryoji Takada Tatsuya Ioka Kazuyoshi Ohkawa Kazuhiro Katayama Hirofumi Akita Hidenori Takahashi Shingo Ohira Teruki Teshima Department of Cancer Survey and Gastrointestinal Oncology Osaka International Cancer InstituteOsaka 541-8567Japan Department of Hepatobiliary and Pancreatic Oncology Osaka International Cancer InstituteOsaka 541-8567Japan Department of Gastroenterological Surgery Osaka University Graduate School of MedicineOsaka 565-0871Japan Department of Surgery Osaka International Cancer InstituteOsaka 541-8567Japan Department of radiation Oncology Osaka International Cancer InstituteOsaka 541-8567Japan

BACKGROUND Preoperative neoadjuvant chemoradiation therapy(NACRT)is applied for resectable pancreatic cancer(RPC).To maximize the efficacy of NACRT,it is essential to ensure the accurate placement of fiducial markers for image-guided ***,no standard method for delivering fiducial markers has been established to date,and the nature of RPC during NACRT remains *** To determine the feasibility,safety and benefits of endoscopic ultrasound-guided(EUS)fiducial marker placement in patients with *** This was a prospective case series of 29 patients(mean age,67.5 years;62.1%male)with RPC referred to our facility for *** EUS guidance,a single gold marker was placed into the tumor using either a 19-or 22-gauge fine-needle aspiration *** differences in daily marker positioning were measured by comparing simulation computed tomography and treatment computed *** In all 29 patients(100%)who underwent EUS fiducial marker placement,fiducials were placed successfully with only minor,self-limiting bleeding during puncture observed in 2 patients(6.9%).NACRT was subsequently administered to all patients and completed in 28/29(96.6%)cases,with one patient experiencing repeat *** migration of gold markers was observed in 1 ***-four patients(82.8%)had surgery with 91.7%(22/24)R0 resection,and two patients experienced complete *** inflammatory changes around the marker were observed in the surgical *** daily position of gold markers showed large positional changes,particularly in the superior-inferior ***,tumor location was affected by food and fluid intake as well as bowel gas,which changes *** EUS fiducial marker placement following NACRT for RPC is feasible and *** RPC is mobile and is affected by not only aspiration,but also food and fluid intake and bowel condition.

关键词： Endoscopic ultrasound-guided fine-needle aspiration Interventional endoscopic ultrasound Pancreatic cancer Fiducial marker Chemoradiation Resectable