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Excited State Properties of Fucoxanthin Aggregates

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Chemical Research in Chinese Universities 2019年第4期35卷 627-635页

作者： ZUO Jialing TAN Liming XU Yi MA Yingchao DONG Jia WANG Peng zhang jianping Department of Chemistry Renmin University of China Beijing 100872 P. R. China

The structure and excited state properties of the H- and J-aggregates of the marine carbonyl carotenoid, fucoxanthin(Fx), were studied by various spectroscopic methods, and compared with those of Fx monomers in polar organic solvents. The fluorescent analysis indicated tliat the higher vibronic states of S2 contribute more to populating the S1 state, from which fluorescent emission mainly originates. Resonance Raman and density functional theory calculations confirmed the ‘card-packed' and chead-to-taiF structures of the H- and J-aggregates of Fx, respectively. An fs time-resolved absorption study proved the coexistence of Si and intramolecular charge transfer relaxation pathways upon excitation to the S2 state for both tlie monomers and aggregates.

关键词： Fucoxanthin aggregate Resonance Raman fs Time-resolved absorption Excited state property Singlet fission

Studies on kinetics of reactions between phycobiliproteins and hydroxyl radicals by a pulse radiolytic technique

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Chinese Science Bulletin 2000年第10期45卷 899-903页

作者： zhang Suping YAO Side WANG Wenfeng XIE Jie zhang jianping ZHAO Jingquan JIANG Lijin Center for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing 100080China Laboratory of Radiation Chemistry Chinese Academy of SciencesShanghai Institute of Nuclear ResearchShanghai 201800China Institute of Photographic Chemistry Chinese Academy of SciencesBeijing 100101China

Scavenging of hydroxyl radical (·OH) by phycobiliproteins (C-phycocyanin, Allophyco- cyanin and R-phycoerythrin) was studied by competitive kinetics methods. Hydroxyl radicals were generated from pulse radiolysis of aqueous systems saturated with nitrous oxide (N2O). The experimental results indicated that the three types of phycobiliproteins are all strong scavengers of· OH, the rate constants are around (2.8-5.6)×109 L·2 mol1 · s 1.

关键词： phycobiliprotein hydroxyl radical scavenging pulse radiolysis rate constant.

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发动机工作状态对排气扩压器流动特性的影响

西南科技大学学报 2024年第2期39卷 92-99页

作者：王韬竣张健平但志宏张松李浩东伍相全西南科技大学制造科学与工程学院四川绵阳621010 中国航空发动机集团有限公司四川燃气涡轮研究院四川绵阳621703

为了准确描述发动机工作状态对高空台排气扩压器流动特性的影响,采用Fluent软件数值模拟分析了3 km和5 km飞行高度,发动机中间状态、小加力状态和最大状态下高空台排气扩压器气流压力、速度、温度的变化规律。结果表明:飞行高度为3 km和... 详细信息

为了准确描述发动机工作状态对高空台排气扩压器流动特性的影响,采用Fluent软件数值模拟分析了3 km和5 km飞行高度,发动机中间状态、小加力状态和最大状态下高空台排气扩压器气流压力、速度、温度的变化规律。结果表明:飞行高度为3 km和5 km时,相同状态下排气扩压器内气流压力、速度、温度变化趋势基本一致。经过排气扩压器扩压减速后,发动机中间状态、小加力状态和最大状态下气流静压增加了12%,21%,25%,气流速度衰减了79%,80%,76%。当发动机工作状态从中间状态转变为最大状态时,排气扩压器内气流温度逐渐升高,波动也越大。

关键词：发动机工作状态排气扩压器流动特性数值模拟分析

Design of integral sliding mode guidance law based on disturbance observer

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Journal of Systems Engineering and Electronics 2024年第1期35卷 186-194页

作者： ZHOU jianping zhang Wenjie ZHOU Hang LI Qiang XIA Qunli School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China School of Informatic Engineering Mianyang Techers’CollegeMianyang 62100China Beijing Institute of Electronic System Engineering Beijing 100854China Beijing Institute of Space Long March Vehicle Beijing 100076China

With the increasing precision of guidance,the impact of autopilot dynamic characteristics and target maneuvering abilities on precision guidance is becoming more and more *** order to reduce or even eliminate the autopilot dynamic operation and the target maneuvering influence,this paper suggests a guidance system model involving a novel integral sliding mode guidance law(ISMGL).The method utilizes the dynamic characteristics and the impact angle,combined with a sliding mode surface scheme that includes the desired line-ofsight angle,line-of-sight angular rate,and second-order differential of the angular *** the same time,the evaluation scenario considere the target maneuvering in the system as the external disturbance,and the non-homogeneous disturbance observer estimate the target maneuvering as a compensation of the guidance *** proposed system’s stability is proven based on the Lyapunov stability *** simulations reveale that ISMGL effectively intercepted large maneuvering targets and present a smaller miss-distance compared with traditional linear sliding mode guidance laws and trajectory shaping guidance ***,ISMGL has a more accurate impact angle and fast convergence speed.

关键词： disturbance observer pilot dynamics integral sliding mode impact angle constraint maneuvering target

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地基沉降载荷作用下压气站管道力学分析

当代化工研究 2024年第8期 96-98页

作者：张建平汪泳吉侯山高杰张亚斌吴峰长庆油田分公司第四采气厂陕西710021 西北大学化工学院陕西710069

针对某天然气管道黄土地基沉降项目,结合数值模拟和现场监测方法对管网应力进行分析,为湿陷区的管网应力分析提供理论依据。数值模拟结果与DH5971监测数据的最大相对误差为9.8%,说明了模拟结果的合理性。管网力学性能的研究表明越靠近... 详细信息

针对某天然气管道黄土地基沉降项目,结合数值模拟和现场监测方法对管网应力进行分析,为湿陷区的管网应力分析提供理论依据。数值模拟结果与DH5971监测数据的最大相对误差为9.8%,说明了模拟结果的合理性。管网力学性能的研究表明越靠近埋地主管部分,管道应力集中现象越明显;管网左侧主管三通处应力为440 MPa,已进入塑性变形阶段。对管网应力释放的研究表明:右侧位移约束消除后,三通处的应力仅为205 MPa,管网应力下降明显;左侧断面应力释放后X向位移变化最大,达到322 mm。

关键词：地基沉降天然气管道应力分析数值模拟

“园林综合实训”课程“项目沉浸式”教学改革实践——2022年风景园林学科调整之后的思考

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豫章师范学院学报 2024年第2期39卷 47-52页

作者：李宝勇赵小利张建平陆金森江西农业大学园林与艺术学院江西南昌330045

“园林综合实训”课程不仅是风景园林专业本科教学重要的实践类课程,也是学生在走入社会前对专业综合技能的一次重要的检验和热身。现基于目前学科和行业发展中面临的新问题和新需求重新梳理课程的培养目标;基于“沉浸式教学”理念,对... 详细信息

“园林综合实训”课程不仅是风景园林专业本科教学重要的实践类课程,也是学生在走入社会前对专业综合技能的一次重要的检验和热身。现基于目前学科和行业发展中面临的新问题和新需求重新梳理课程的培养目标;基于“沉浸式教学”理念,对课程教学内容和教学进度安排进行改革优化,并采用校园实际场地营建项目的模式进行教学实践;通过分阶段介绍实训教学环节内容和要点,总结教学改革的成效与不足,提出进一步的改进措施,为提升综合实训课程教学效果和风景园林专业教学改革提供参考与借鉴。

关键词：风景园林 “园林综合实训”课程沉浸式教学改革思考

进食方式与老年住院患者坐起能力的相关性研究

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老年医学与保健 2024年第4期30卷 1145-1148页

作者：李美萍吴颖张见平朱怡莹陈琦上海市普陀区利群医院康复科上海200333 上海市普陀区利群医院急诊医学科上海200333

目的探讨进食方式与老年住院患者坐起能力的关系。方法回顾性分析2023年5月—2024年3月在上海市普陀区利群医院老年科住院的169例老年患者的临床资料。将所有患者按照进食方式分为口进食组(n=102)和鼻饲组(n=67)。观察并比较2组患者的... 详细信息

目的探讨进食方式与老年住院患者坐起能力的关系。方法回顾性分析2023年5月—2024年3月在上海市普陀区利群医院老年科住院的169例老年患者的临床资料。将所有患者按照进食方式分为口进食组(n=102)和鼻饲组(n=67)。观察并比较2组患者的一般资料和坐起能力,并应用二元Logistic回归方法分析进食方式、年龄、性别和疾病类型对坐起能力的影响。结果与口进食组相比,鼻饲组患者的年龄更大、卧床时间更长、脑卒中和脑卒中合并其他疾病的比例更高,差异均有统计学意义(均P<0.05)。鼻饲组患者的坐起能力显著低于口进食组(P<0.001)。Logistic回归分析显示,鼻饲进食(OR=0.007,95%CI:0.0010.055)、年龄≥85岁(OR=0.257,95%CI:0.0810.819)、脑卒中合并呼吸/心血管疾病(OR=0.140,95%CI:0.0250.789)是坐起能力差的独立危险因素(均P<0.05)。结论鼻饲进食方式、高龄和脑卒中合并其他疾病可能是老年住院患者坐起能力差的独立危险因素。针对不同特点的患者,可采取个体化的康复和营养干预措施。

关键词：老年进食方式坐起能力鼻饲康复营养

Characterization of melanin produced by a wild-type strain of Bacillus cereus

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Frontiers in Biology 2007年第1期2卷 26-29页

作者： zhang jianping CAI Jun DENG Yinyue CHEN Yuehua REN Gaixin Department of Microbiology College of Life SciencesNankai UniversityTianjin Key Laboratory of Microbial Functional GenomicsTianjin 300071China

Bacillus cereus 58(Bc58)is a UV-resistant wild type strain that has an ability to produce a sorrel pigment induced by *** Fourier-transform infrared(FT-IR)spectra and chemical tests of its pigment are similar to that of the standard melanin(Sigma).A bioassay shows that the LC50 of a Bacillus thuringiensis(Bt)formulation added with the melanin of Bc58 and exposed to UV for 5 h is 16.1μg/m1,which is similar to that of the Bt formulation without UV treatment,however,it is almost double that of the Bt formulation exposed to UV without the melanin of *** result of SDS-PAGE indicates that the melanin of Bc58 can protect the insecticidal crystal proteins from *** suggests that it is an excellent UV protective agent for the insecticidal crystal proteins of the Bt formulation.

关键词： Bacillus cereus melanin UV protection

Formation and Optical Properties of ZnO:ZnFe_(2)O_(4) Superlattice Microwires

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Nano Research 2010年第5期3卷 326-338页

作者： Yun Li Guozhang Dai Chunjiao Zhou Qinglin zhang Qiang Wan Limin Fu jianping zhang Ruibin Liu Chuanbao Cao Anlian Pan Yunhong zhang Bingsuo Zou State Key Laboratory of Chemo/biosensing and Chemometrics(CBSC) Hunan UniversityChangsha 410082China School of Materials Science and Engineering(MSE) Beijing Institute of TechnologyBeijing 100081China Chemistry Department Renmin University of ChinaBeijing 100872China

Pure ZnO hexagonal microwires and Fe(Ⅲ)-doped ZnO microwires(MWs)with a novel rectangular cross section were synthesized in a confined chamber by a convenient one-step thermal evaporation *** oriented attachment mechanism is consistent with a vapor-solid growth ***(PL)and Raman spectroscopy of the Fe(Ⅲ)-doped ZnO MWs and in situ spectral mappings indicate a quasi-periodic distribution of Fe(Ⅲ)along a one-dimensional(1-D)superlattice ZnO:ZnFe_(2)O_(4) wire,while PL mapping shows the presence of optical multicavities and related *** PL spectra at room temperature show weak near-edge doublets(376 nm and 383 nm)and a broad band(450-650 nm)composed of strong discrete lines,due to a 1-D photonic crystal *** a 1-D coupled optical cavity material may find many applications in future photonic and spintronic devices.

关键词： ZnO superlattice microwire micro-photoluminescence micro-Raman spectroscopy