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Novel hyperbranched polyimides from 2,6,12-triaminotriptycene

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Chinese Chemical Letters 2008年第9期19卷 1127-1130页

作者： Zhen xu Xing Quan Xiong Lin Cheng Department of Materials Science ＆ Engineering Huaqiao University Quanzhou 362021 China

The monomer 2,6,12-triaminotriptycene was synthesized and the structure was confirmed by IR and 1h NMR spectra. hyperbranched polyimides modified with different terminal groups were obtained from precursors, anhydride- and aminoterminated hyperbranched poly（amic acid）s from polymerization of A2 ＋ B3 system. From gel permeation chromatograrn （GPC） characterization, representative products had high molecular weight. All polymers had good solubility in ChCl3, DMF and tetrahydrofuran （ThF）, and performed no detective Tgs in the range of 50-300 ℃ and high Tds above 455 ℃ when 5% weight loss.

关键词： Triptycene hyperbranched polymer Polyimides

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结直肠癌的免疫治疗

生物化学与生物物理进展 2024年第10期51卷 2570-2586页

作者：许浩然赵肖仪聂贺王慧张清淋占强南京医科大学附属无锡人民医院消化内科无锡市人民医院南京医科大学无锡医学中心国家消化系统疾病临床研究中心(西安)江苏省分中心无锡214023

改善结直肠癌(colorectal cancer,CRC)患者的预后具有重要的临床和社会意义。免疫治疗是一种新兴的肿瘤治疗方式,免疫检查点抑制剂已在DNA错配修复缺陷/高微卫星不稳定型CRC的治疗中实现了良好的临床转化,占绝大多数的DNA错配修复完整/... 详细信息

改善结直肠癌(colorectal cancer,CRC)患者的预后具有重要的临床和社会意义。免疫治疗是一种新兴的肿瘤治疗方式,免疫检查点抑制剂已在DNA错配修复缺陷/高微卫星不稳定型CRC的治疗中实现了良好的临床转化,占绝大多数的DNA错配修复完整/微卫星稳定型CRC患者却很难在该疗法中获益。免疫疫苗、过继性细胞疗法等其他免疫疗法的临床研究也在积极推进中,虽然展示了一定的良性结果,但仍面临着难以有效突破肿瘤抑制性微环境等诸多问题而未能获得实质性进展。本文以各种免疫治疗方案相关的临床试验为主线进行综述,以期明确CRC免疫治疗的进展,为更优治疗方案的探索提供依据。

关键词：结直肠癌免疫治疗免疫检查点抑制剂免疫疫苗过继性细胞疗法

PKinetics analysis of the enzymatic hydrolysis of cellulose from straw stalk

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Chinese Journal Of Geochemistry 2013年第1期32卷 41-46页

作者： ChEN Kun xu Longjun BI Zhiming FU Zhilei State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University College of Safety Engineering Chongqing University of Science and Technology

The effects of several parameters on the simultaneous saccharification and fermentation of straw stalk for ethanol fuel production were investigated on the basis of orthogonal experiments. The parameters include temperature and time of fermentation, quantity and proportion of yeast inoculation, as well as cellulase dosage. An ethanol yield of 0.183 g/g was obtained from the straw stalk pretreated with diluted acid under determined optimum conditions. These conditions were: fermentation temperature: 38℃; fermentation time: 72 h; yeast inoculation quantity: 15%; yeast inoculation proportion: 2:1; and cellulose enzyme dosage: 20 U/g. The relationship between ethanol concentration c and fermentation time t is presented as follows, c=abt/(1+bt). The rate constant k of straw stalk hydrolysis by the cellulose enzyme depends on hydrolysis time, as described by k=k1t-h. Therefore, straw stalk hydrolysis reaction by the cellulose enzyme is fractal-like.

关键词：纤维素酶酶水解动力学分析秸秆发酵时间反应速率常数乙醇燃料发酵生产

Simulations of h-Mode Plasmas in Tokamak Using a Complete Core-Edge Modeling in the BALDUR Code

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Plasma Science and Technology 2012年第9期14卷 778-788页

作者： y.PIANROJ T.ONJUN School of Manufacturing Systems and Mechanical Engineering Sirindhorn International Institute of TechnologyThammasat UniversityPathum Thani 12121Thailand

A theory-based model for predicting the pedestal formation in both ion and electron temperatures, and hydrogenic and impurity density is developed and implemented in the 1.5D BALDUR codes for self-consistently simulating h-mode plasma in tokamak. In the simulation, the transports around pedestal, including the electron and ion thermal, hydrogenie and impurity particle transports are calculated using an （Mixed B/gB） model, which is modified to anomalous semi-empirical mixed Bohm/gyro-Bohm include the effects of ωE×B flow shear and magnetic shear. Because of the reduction of transport, the pedestal can be formed. For a preliminary test, this core-edge model is used to simulate the temporal evolution of plasma current, temperature, and density profiles for DIII-D discharges. It is found that the simulations successfully reproduce the experimental results. A statistical analysis, including RMSE and offset, is used to quantify the agreement between the prediction and the corresponding experimental results. The simulation results show an agreement with average RMSE of 11.87%, 14.53%, 7.59% and 12.21% for electron temperature, ion temperature, electron density, and deuterium density profiles, respectively. In addition, it is found that the suppression function developed is effective only in the edge region.

关键词： ITER pedestal h-mode BALDUR fusion performance transport

Effect of CeO_2 preparation method and Cu loading on CuO/CeO_2 catalysts for methane combustion

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Journal of Natural Gas Chemistry 2009年第4期18卷 458-466页

作者： Weiling yang Dao Li Dongmei xu Xingyi Wang Key Laboratory for Advanced Materials Research Institute of Industrial Catalysis East China University of Science and Technology Shanghai 200237 China

CeO2 was synthesized by sol-gel, hydrothermal, nitrate thermal decomposition methods, respectively, and used as support to prepare CuO/CeO2 catalysts. According to characterization and reaction results, preparation method of CeO2 had a great influence on the physicochemical properties and activities of CuO/CeO2 catalysts. CuO with high dispersion and strong interaction with CeO2 was highly active in methane combustion, while CuO particles less associated with CeO2 showed less activity. The CuO catalyst supported on CeO2 which was prepared via nitrate thermal decomposition method showed the largest area, the smallest particle size, the highest dispersion of copper species and strong support metal interactions. Therefore, it presented the highest redox ability and activity for methane combustion. Activities of the catalysts with different copper content kept increasing until 5% Cu loading and from then on kept constant. Moreover, methane conversion decreased as methane space velocities increased on CuO/CeO2 catalyst. Addition of CO2 to the feed did not produce a significant effect on the catalytic activity, but the presence of h2O provoked a remarkable decrease on the activity of CuO/CeO2 catalyst.

关键词： ceria CuO/Ce02 methane combustion

ESTIMATION OF RELATIVE BLOOD VOLUME IN hEAD AND NECK TUMORS

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波谱学杂志 2002年第1期19卷 101-102页

作者： R.h.WU R.Bruening J.MA C.BERChTENBREIThER R.JUND h.B.RAO X.h.xu M.REISER Shantou University Medical College China Klinikum GrosshadernUniversity of MunichGermany Klinikum Grosshadern University of MunichGermany Dalian Medical University China Shantou University Medical College China

Introduction: The calculation of relative blood volume in head and neck tumor with MR imaging is anew approach that may provide additional hemodynamic information relevant to both untreated and treated tumors. This hemodynamic information is especially useful for the differentiation between viable tumor and postsurgical changes or radiation induced scar, and is also beneficial for tumor staging and tumor biopsy.

关键词： maps ESTIMATION OF RELATIVE BLOOD VOLUME IN hEAD AND NECK TUMORS

PEGylated liposomal photosensitizers as theranostic agents for dual-modal photoacoustic andffuorescence imaging-guided photodynamic therapy

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Journal of Innovative Optical health Sciences 2019年第3期12卷 32-40页

作者： hao xu yubin Liu Junle Qu Zhen yuan College of Optoelectronic Engineering Shenzhen University Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province ShenzhenGuangdongP.R.China Faculty of health Sciences University of Macao TaipaMacao SAR 999078P.R.China

The photosensitizer(PS)as photodynamic therapy(PDT)agent,can also serve as the contrast agent for dual-modalffuorescence imaging(FLI)and photoacoustic imaging(PAI)for precise cancer *** this study,the PAI capability of commercial PS,benzoporphyrin derivative monoacid ring-A(BPD)were examined and compared with that from the other PSs and dyes such as TPPS_(4),Cy5 dye and *** discovered that BPD exhibited its advantage as contrast agent for ***,BPD can also serve as the contrast agent for enhanced *** particular,the PEGylated nanoliposome(PNL)encapsulated BPD(LBPD)was produced for contrast enhanced dual-modal FLI and PAI and imaging-guided high-efficiency *** FLI and PAI results demonstrated the significant accumulation of LBPD both within and among individual tumor during 24 h monitoring for in vivo experiment ***-vitro and in-vivo PDT tests were also performed,which showed that LBPD have higher PDT efficiency and can easily break the blood vessel of tumor tissues as compared to that from *** was discovered that LBPD has great potentials as a diagnosis and treatment agent for dual-modal FLI and PAI-guided PDT of cancer.

关键词： Liposome photosensitizer photodynamic therapy photoacoustic imaging ffuorescence imaging

土壤可溶性有机硫的微生物分解与植物利用机制

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植物营养与肥料学报 2024年第3期30卷 587-604页

作者：姚瑞琪钭从越王英凡刘秀吴良欢马庆旭浙江大学环境与资源学院浙江省农业资源与环境重点实验室浙江杭州310058 浙江大学环境与资源学院/教育部环境修复与生态健康重点实验室浙江杭州310058

硫(S)是植物生长必需的营养元素,但是近年来植物的潜在缺硫现象在全球范围内普遍发生。可溶性有机硫(DOS)作为土壤硫的一种重要形态,可被微生物快速分解为硫酸盐而被植物吸收,因此,明确土壤DOS含量、组成、微生物分解机制和植物利用过... 详细信息

硫(S)是植物生长必需的营养元素,但是近年来植物的潜在缺硫现象在全球范围内普遍发生。可溶性有机硫(DOS)作为土壤硫的一种重要形态,可被微生物快速分解为硫酸盐而被植物吸收,因此,明确土壤DOS含量、组成、微生物分解机制和植物利用过程有利于解决潜在缺硫问题。本文综述了土壤DOS[可溶性蛋白质、含硫氨基酸蛋氨酸(Met)和半胱氨酸(Cys)]的微生物分解过程及植物吸收利用机制。可溶性蛋白质可以在数天内分解成无机硫(SO42-),而含硫氨基酸可以在数分钟到数小时内被分解。微生物吸收含硫氨基酸后的几分钟到几小时内,可将含硫氨基酸中的碳、氮和硫分别以CO^(2)、Nh^(4+)和SO_(4)^(2-)的形式释放到微生物体外,释放的无机硫会被微生物再次利用以满足其生长发育。微生物能迅速利用DOS(Met、Cys),当其被微生物同化时,其原始分子结构决定了其转化成的生物大分子,从而影响DOS与SO_(4)^(2-)之间的转化速率。Cys的硫醇基(h-S-C)易被氧化,因此微生物吸收利用Cys后SO_(4)^(2-)释放量高于Met。小麦和油菜对Met和Cys的摄取量随着其供应量的增加而增加,田间条件下小麦和油菜可吸收0.63%~2.2%的外源Cys和0.4%~2.1%的外源Met。Met和Cys在植物氮营养中的作用有限,但它们在植物硫营养中的作用非常重要,约占植物硫吸收总量的10%。土壤DOS可被微生物快速分解,产生的SO_(4)^(2-)可被植物快速吸收利用。即使存在土壤微生物的激烈竞争,植物也能够吸收完整的分子态有机硫(Met和Cys),DOS是植物生长的重要硫源,其吸收主要发生在富含有机质的土壤中。

关键词：缺硫含硫氨基酸硫分解硫的生物利用率植物硫吸收

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满月光环境下夜视镜对视觉绩效的影响

海军军医大学学报 2024年第7期45卷 905-910页

作者：陈剑政陈涛曹瑞丹张建英许丽芬张作明苏玉婷空军军医大学航空航天医学系航空临床医学中心教育部航空航天医学重点实验室西安710032 海军青岛特勤疗养中心感官生理训练科青岛266071 空军军医大学第一附属医院空勤科西安710032

目的研究夜视镜(NVG)对视觉绩效的影响,为开展NVG地面模拟训练提供试验依据。方法招募20名视力正常的志愿者,佩戴NVG在满月光环境(0.1 lx)下检测静态远视力、深径觉误差、动态视力(DVA,3.0、4.5、6.0、7.5 km/h运动速度)、视觉认知时间... 详细信息

目的研究夜视镜(NVG)对视觉绩效的影响,为开展NVG地面模拟训练提供试验依据。方法招募20名视力正常的志愿者,佩戴NVG在满月光环境(0.1 lx)下检测静态远视力、深径觉误差、动态视力(DVA,3.0、4.5、6.0、7.5 km/h运动速度)、视觉认知时间、视觉搜索时间5项视觉绩效指标,通过与裸眼在曙暮光环境(15 lx)下测得的相同指标的比较评估满月光环境下NVG对视觉绩效的影响。对比佩戴NVG和裸眼在标准暗室中对红、蓝光源(2 cd/m^(2))位置关系的判断能力。结果与裸眼在曙暮光环境下相比,佩戴NVG在满月光环境下的4种运动速度(3.0、4.5、6.0、7.5 km/h)的DVA均降低(均P0.05)。佩戴NVG正确判断红、蓝光源远近位置关系的得分低于裸眼(P=0.001),佩戴NVG更容易误判红色光源距离自己较近(P=0.001)。结论DVA、深径觉和视觉搜索能力是NVG提升视觉绩效的薄弱点,NVG地面模拟训练应重视动态目标的搜索、识别及深径觉训练。佩戴NVG飞行时不能把颜色光源作为距离判断的线索,应注重NVG和裸眼的交替使用,增强获取系统信息和建立周围情景意识的能力。

关键词：夜视镜视觉绩效夜视训练飞行人员满月光环境