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Chinese Journal of Chemical Engineering 2023年第8期60卷 194-204页

作者： Xiaolin Pan Mengyuan gao Yun Wang Yanping He Tian Si Yanlin Sun School of Chemical Engineering Kunming University of Science and TechnologyKunming 650504China

Drug-loaded microspheres are significant for the development of modern pharmaceutical products. It is well known that the taken of aspirin for long-term increases the risk of serious gastrointestinal complications, therefore a controllable delivery of aspirin is of importance to lighten those side effects. In this work, poly(lactic acid)(PLA) was chosen as the carrier to prepare PLA-aspirin microspheres by using the traditional and the improved solvent evaporation methods. It was found that no matter which experimental condition was, the encapsulation efficiency of aspirin was higher by using the improved method than that of the traditional method. Specifically, when the concentration of polyvinyl alcohol = 1%(mass),the polymer concentration = 1:20, the oil/water rate = 1:2.5, PLA-aspirin microspheres were obtained via the improved method with a high yield of 82.83%(mass) and an encapsulation efficiency of 44.09%. PLAaspirin microspheres were then prepared continuously using the improved method, which further enhanced the encapsulation efficiency to 54.56%. Approximate 85% aspirin released from microspheres within 7 days. Obvious degradation which was represented by reduction on hardness was observed by soaking microspheres in PBS for 60 days. This work is of interest because it provides a continuous route to prepare PLA-aspirin microspheres continuously with a high drug encapsulation efficiency.

关键词： Aspirin Degradation Foam-transfer Microspheres Poly(lactic acid) Slow-release

Unmanned aerial vehicle swarm mission reliability modeling and evaluation method oriented to systematic and networked mission

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Chinese Journal of Aeronautics 2021年第2期34卷 466-478页

作者： Lizhi WANG Xuejiao ZHAO Yuan ZHANG Xiaohong WANG Tielin MA Xia gao Unmanned System Institute Beihang UniversityBejing 100083China School of Reliability and Systems Engineering Beihang UniversityBeijing 100083China Digital Twinning and System Engineering Research Center Yunnan Innovation InstituteBeihang UniversityBejing 650233China Key Laboratory of Advanced Technology of Intelligent Unmanned Flight System of M inistry of Industry and Information Technology Beijing 100083China School of Astronautics Beihang UniversityBejing 100083China

With the development of Unmanned Aerial Vehicle(UAV) system autonomy, network communication technology and group intelligence theory, mission execution in the form of a UAV swarm will be an important realization of future applications. Traditional single-UAV mission reliability modeling methods have been unable to meet the requirements of UAV swarm mission reliability modeling. Therefore, the UAV swarm mission reliability modeling and evaluation method is proposed. First, aimed at the interdependence among the multiple layers, a multi-layer network model of a UAV swarm is established. At the same time, based on the system having the following characteristics—using a mission chain to complete the mission and applying the connectivity of the mission network—the mission network model of a UAV swarm is established. Second, vulnerability and connectivity are selected as two indicators to reflect the reliability of the mission, and aimed at random attack and deliberate attack, vulnerability and connectivity evaluation methods are proposed. Finally, the validity and accuracy of the constructed model are verified through simulations,and the model and selected indicators can meet the reliability requirements of the UAV swarm mission. In this way, this study provides quantitative reference for UAV-swarm-related decisionmaking work and supports the development of UAV-swarm-related work.

关键词： Complex networks Connectivity Mission reliability Unmanned Aerial Vehicles(UAV) Vulnerability

Separation of galena and chalcopyrite using the difference in their surface acid corrosion characteristics

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International Journal of Minerals,Metallurgy and Materials 2023年第11期30卷 2157-2168页

作者： Haiyun Xie Jialing Chen Pei Zhang Likun gao Dianwen Liu Luzheng Chen Faculty of Land and Resources Engineering Kunming University of Science and TechnologyKunming 650093China yunnan Key Laboratory of Green Separation and Enrichment of Strategic Mineral Resources Kunming 650093China

Galena(PbS)and chalcopyrite(CuFeS_(2))are sulfide minerals that exhibit good floatability ***,efficiently separating them via common flotation is ***,a new method of surface sulfuric acid corrosion in conjunction with flotation separation was proposed,and the efficient separation of galena and chalcopyrite was successfully *** angle test results showed a substantial decrease in surface contact angle and a selective inhibition of surface floatability for corroded ***,the contact angle and floatability of corroded chalcopyrite remained almost *** electron microscope results confirmed that sulfuric acid corrosion led to the formation of a dense oxide layer on the galena surface,whereas the chalcopyrite surface remained unaltered.X-ray photoelectron spectroscopy results showed that the chemical state of S^(2-)on the surface of corroded galena was oxidized to SO_(4)^(2-).A layer of hydrophilic PbSO4was formed on the surface,leading to a sharp decrease in galena ***,new hydrophobic CuS_(2),CuS,and Cu_(1-x)Fe_(1-y)S_(2-z)species exhibiting good floatability were generated on the chalcopyrite ***,theoretical analysis results were further verified by corrosion–flotation separation *** galena–chalcopyrite mixture was completely separated via flotation separation under appropriate corrosion acidity,corrosion temperature,and corrosion time.A novel approach has been outlined in this study,providing potential applications in the efficient separation of refractory copper–lead sulfide ore.

关键词： surface acid corrosion galena chalcopyrite flotation separation efficiency

Rayleigh wave phase velocity tomography and strong earthquake activity on the southeastern front of the Tibetan Plateau

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Science China Earth Sciences 2014年第11期57卷 2532-2542页

作者： WANG Qiong gao Yuan Institute of Earthquake Science China Earthquake Administration Institute of Geophysics China Earthquake Administration

To investigate the relationship between velocity structure and earthquake activity on the southeastern front of the Tibetan Plat- eau, we make use of continuous observations of seismic ambient noise data obtained at 55 broadband stations from the regional yunnan Seismic Network. These data are used to compute Rayleigh wave Green＇s Functions by cross-correlating between two stations, extracting phase velocity dispersion curves, and finally inverting to image Rayleigh wave phase velocity with periods between 5 and 34 s by ambient noise tomography. The results tie structures in the studied region. Phase velocity anomalies show significant lateral variations in crustal and uppermost man- at short periods （5-12 s） are closely related to regional tectonic features such as sediment thickness and the depth of the crystalline basement. The Sichuan-yunnan rhombic block, enclosed by the Honghe, Xiaojiang and Jianchuan faults, emerges as a large range of low-velocity anomalies at periods of 16-26 s, that in- verts to high-velocity anomalies at periods of 30-34 s. The phase velocity variation in the vicinity of the Sichuan-yunnan rhombic block suggests that the low-velocity anomaly area in the middle-lower crust may correspond to lower crustal channel- ized flow of the Tibetan Plateau. The spatial distribution of strong earthquakes since 1970 reveals that the yunnan region is inhomogeneous and shows prominent characteristics of block motion. However, earthquakes mostly occur in the upper crust, with the exception of the middle-yunnan block where earthquakes occur at the interface zone between high and low velocity as well as in the low-velocity zones, with magnitudes being generally less than 7. There are few earthquakes of magnitude 5 at the depths of 15-30 km, where gather earthquakes of magnitude 7 or higher ones which mainly occur in the interface zone between high and low velocities with others extending to the high-velocity abnormal zone.

关键词： southeastern front of the Tibetan Plateau yunnan region ambient noise cross-correlation Rayleigh wave surfacewave tomography

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Pollinator attraction in Cornus capitata (Cornaceae): the relative role of visual and olfactory cues

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Journal of Plant Ecology 2015年第2期8卷 173-181页

作者： Bo Song Yang Niu Jürg Stöcklin gao Chen De-Li Peng Yong-Qian gao Hang Sun Key Laboratory for Plant Diversity and Biogeography of East Asian Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming 650201YunnanChina Section of Plant Ecology Institute of BotanyUniversity of BaselSchönbeinstrasse 6Basel 4056Switzerland Kunming Botanical Garden Kunming Institute of BotanyChinese Academy of Sciences132 Lanhei RoadKunming 650201YunnanChina Department of Ecology and Environmental Engineering Yunnan Forestry Technological College1 Chuanjin RoadKunming 650224YunnanChina

Aims it is generally accepted that visual displays and floral scent play important roles in communication between flowering plants and their ***,the relative role of visual and olfactory cues in pollinator attraction is largely *** this study,we determined the roles of both types of cue in attracting pollinators to Cornus capitata,a medium sized tree with each capitulum sur-rounded by four large,white,petaloid *** Pollinator observations and pollination experiments were con-ducted in a natural population;the inflorescences’visual and olfactory signals were characterized by spectral and chemical analyses;the responses of pollinators to visual and olfactory cues were tested using dual-choice behavioural bioassays;the relative roles of visual and olfactory cues in pollinator attrac-tion were tested by comparing the responses of pollinators to inflorescences subjected to three experimental treatments(intact,all bracts removed,and capitulum removed)within the natural *** Findings For fruit set,*** is entirely dependent on pollinators,with a bee,Anthophora sp.,being the main *** present high colour distance and green contrast against the *** volatile compounds in the floral scent were detected,most of which have previously been reported to be attractive to a broad spectrum of bee *** bioassays showed that both,visual cues alone and olfactory cues alone,are attractive to pollinating ***,vis-ual cues alone attracted significantly more approaches than olfactory cues alone,while olfactory cues alone elicited a significantly higher landing percentage than visual cues *** finding suggests that,in the ***-Anthophora ***,visual cues are mainly used for location from long distances,while olfactory cues mainly aid landing from short *** results indicate that different modalities of floral cues should be considered together to understand fully

关键词： bract floral scent olfactory cues spectral reflectance visual cues

Reproductive biology of Magnolia sinica(Magnoliaecea),a threatened species with extremely small populations in yunnan,China

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Plant Diversity 2016年第5期38卷 253-258页

作者： Ye Chen gao Chen Jing Yang Weibang Sun Kunming Botanical Garden Kunming Institute of BotanyChinese Academy of SciencesKunming650201 YunnanChina University of Chinese Academy of Sciences 100049 BeijingChina

Magnolia sinica is one of the most threatened trees endemic to Southeast *** on our investigations,only 52 individuals and eight populations are found in the *** has been categorized as Critically Endangered on the IUCN Red List and identified as a "Plant Species with Extremely Small Populations(PSESP)".Its fruit/seed set is very low and seedlings are rarely found in the *** is hypothesized that it may encounter obstacles to reproductive *** study,therefore,focuses on its reproductive biology,knowledge of which is essential for effective *** of this species are protogynous and nocturnal,and possess a two-day rhythm of sexual *** the first night of anthesis,the flowers are in the pistillate stage during which tepals open at dusk and close approx.1 h later(except for the open outer ones).They remain closed until the next afternoon,when flowers,now in the staminate stage,re-open and remain so until the tepals *** beetles enter into the flowers and remain trapped throughout the night as the flower closes,during which time they feed on ***-gathering bees are found to visit the re-opened flowers and the beetles are released during this *** species of Pleocomidae and Curculionidae beetles appear to be effective *** is a self-compatible,pollinator-dependent species,and its fruit/seed set can be significantly increased by *** functional seed dispersers have been found in its extant natural *** findings suggest that it may face both pollination and seed disperser insufficiencies in its current fragmented habitats,which may account for its low *** we propose conservation strategies based on our findings.

关键词： Magnolia sinica PSESP Flowering process Pollination Seed dispersal Germination

The characteristics and significance of pure nitrogen fluid inclusions in Xikuangshan copper deposit,Dongchuan,yunnan of China

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Chinese Journal Of Geochemistry 2012年第1期31卷 78-84页

作者： YE Lin LIU Yuping YANG Yulong gao Wei State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of SciencesGuiyang 550002China Graduate University of Chinese Academy of Sciences Beijing 100049China

Nitrogen is an important gas-phase element in geological fluid,and normally hosted in mineralizing fluid,in which the content is very *** 100% mol pure nitrogen inclusion was discovered in copper-bearing quartz vein from Xikuangshan copper deposit,Dongchuan,yunnan Province in this *** is between 3 and 5 μm,in shape of ellipse,occurring in group or independence without obvious orientation,and co-existed with primary gas-liquid *** analysis by using laser Raman spectroscopy shows its composition is dominated by nitrogen with minor *** concentration of N2 may be the necessary and sufficient condition for forming this kind of *** is suggested that there are two genesis modes of pure N2 inclusion in the deposit,oxida-tion-devolativation of mantle matter and trap of metasomatic fluid in organic matter decomposition in Luoxue For-mation *** conclusion,pure N2 inclusion hardly presents in the ore-forming fluids,which providing a new evidence for the genesis of Xikuangshan type copper deposit.

关键词：中国云南锡矿山流体包裹体纯氮铜矿东川激光拉曼光谱充分必要条件

High regional genetic differentiation of an endangered relict plant Craigia yunnanensis and implications for its conservation

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Plant Diversity 2016年第5期38卷 221-226页

作者： Jing Yang Zerui gao Weibang Sun Changqin Zhang Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of Sciences yunnan Tobacco Industrial Hi-tech Material CO. LTD Kunming Botanical Garden Kunming Institute of BotanyChinese Academy of Sciences

Of the genus Craigia,widespread in the Tertiary,only two relict species survived to modern *** species is now possibly extinct and the other one,Craigia yunnanensis,is severely *** surveys have located six *** populations in yunnan province,southwest *** fluorescent amplified fragment length polymorphism(AFLP),the genetic diversity and population structure of these populations were *** was found that genetic diversity of *** was moderate at the species level,but low at regional and population *** of population structure showed significant genetic differentiation between Wenshan and Dehong regions,apparently representing two geographically isolated for long time *** are also clear indications of isolation between populations,which,together with anthropogenically caused decline of population size,will lead to general loss of the species genetic variation with subsequent loss of adaptive *** conserve the genetic integrity of ***,we recommend that ex-situ conservation should include representative samples from every population of the two differentiated regions(*** and Dehong).The crosses between individuals originated from different regions should be avoided because of a high risk of outbreeding *** all the extant populations of *** are in unprotected areas with strong anthropogenic impact,there is no alternative to reintroduction of *** into suitable protected locations.

关键词： Craigia yunnanensis Isolation AFLP Genetic diversity Population genetic structure Conservation genetics

Effects of highway construction on soil quality in the Longitudinal Range-Gorge Region in yunnan Province

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Chinese Science Bulletin 2007年第A02期52卷 192-202页

作者： ZHAO ShuQing CUI BaoShan gao LiNa LIU Jie State Key Joint Laboratory of Environmental Simulation and Pollution Control School of Environment Beijing Normal UniversityBeijing 100875 China

在在西南的中国的纵的范围峡区域包围生态系统之上的高速公路建设的影响基于地调查和试验性的分析被检测。我们在达利上进行了研究(从达利城市到丽江城市)省的道路， Dabao (从达利城市到 Baoshan 城市)高速公路和 Baolong (从 Baoshan... 详细信息

在在西南的中国的纵的范围峡区域包围生态系统之上的高速公路建设的影响基于地调查和试验性的分析被检测。我们在达利上进行了研究(从达利城市到丽江城市)省的道路， Dabao (从达利城市到 Baoshan 城市)高速公路和 Baolong (从 Baoshan 城市到 Longling 县)在纵的范围峡区域的高速公路用包围土壤质量的 space-for-time 替换，和预言的补习的方法玷污质量在包围上检测高速公路建设的效果。结果显示出那：(1 ) 自然、栽培的土壤质量上的高速公路建设的效果是重要的，并且效果比在使用的高速公路的时期在高速公路建设的时期是更重要的。(2 ) 高速公路建设的效果是更明显的在上比 upslope，和效果范围下坡是 200 m 在上下坡，当时 upslope 上的 150 m。(3 ) 土壤补习主要与高速公路建设，高速公路服务时间，植被恢复，土壤有机物和土壤的效果程度有关全部的氮，在哪个之中，高速公路建设是最重要的因素。(4 ) 当植被范围能被恢复到 30% 原来的状况时，土壤质量罐头在 10 年以后被补救到 44% 原来的状况，一旦它被破坏，显示土壤富饶补习是相当困难的。

关键词：纵向岭谷区云南公路土壤

年轻和老年小鼠脂肪来源干细胞生物学特性对比

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中国组织工程研究 2025年第19期29卷 4063-4068页

作者：林美玉姚翔高景赵玺龙潘兴华阮光萍解放军联勤保障部队第九二〇医院基础医学实验室云南省昆明市650032 干细胞与免疫细胞生物医药技术国家地方联合工程研究中心云南省昆明市650032 云南省细胞治疗技术转化医学重点实验室云南省昆明市650032

背景:脂肪来源干细胞具有抗衰老的作用,但来自不同年龄供者的脂肪来源干细胞是否有区别,还需深入研究。目的:对比老年和年轻小鼠脂肪来源干细胞的生物学特性。方法:分别从8周龄、14周龄C57BL小鼠脂肪组织中提取脂肪来源干细胞,对比分析... 详细信息

背景:脂肪来源干细胞具有抗衰老的作用,但来自不同年龄供者的脂肪来源干细胞是否有区别,还需深入研究。目的:对比老年和年轻小鼠脂肪来源干细胞的生物学特性。方法:分别从8周龄、14周龄C57BL小鼠脂肪组织中提取脂肪来源干细胞,对比分析老年和年轻小鼠脂肪来源干细胞的细胞周期、凋亡、增殖能力的差异,定量PCR和Western blot检测老年和年轻小鼠脂肪来源干细胞衰老相关P21、P27基因和蛋白的表达。结果与结论:与老年小鼠脂肪来源干细胞相比,年轻小鼠脂肪来源干细胞更有活力,形态更规则,凋亡更少,增殖更快,衰老相关P21、P27基因和蛋白表达量更低,说明年轻小鼠脂肪来源干细胞具有更好的抗衰老作用。

关键词：脂肪来源干细胞脂肪组织年轻老年小鼠抗衰老