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中国科学：地球科学 2018年第3期48卷 331-339页

作者：曹世雄刘玉洁苏蔚郑鑫怡余中淇中央民族大学经济学院北京100081 北京林业大学经济管理学院北京100083

生态环境保护是维护生态系统健康、改善生态系统服务功能、增加人类社会福祉的有效途径.然而,生态系统服务价值(VEs)的获得必然会产生成本投入,传统的生态系统服务价值评估方法忽略了相关成本分析,给土地规划造成了混乱,不利于环境保护... 详细信息

生态环境保护是维护生态系统健康、改善生态系统服务功能、增加人类社会福祉的有效途径.然而,生态系统服务价值(VEs)的获得必然会产生成本投入,传统的生态系统服务价值评估方法忽略了相关成本分析,给土地规划造成了混乱,不利于环境保护和社会经济的可持续发展.为了认知生态系统服务价值和净价值(NEs)的差异,改进生态系统服务评价方法,该研究在生态系统服务价值研究的基础上,评估了1952年以来中国大陆主要生态系统(包括农田、草地、林地和湿地)服务净价值及其变化.结果表明,中国陆地生态系统年均服务净价值为10.0×10~3元/公顷,为服务价值的35.1%,草地生态系统服务净价值最低,为-0.7×10~3元/公顷;中国大陆农田、草地、林地和湿地2014年实现生态系统服务净价值7.2×10^(12)元,是全国国民净收益(居民可支配收入与政府收入的总和)25.6×10^(12)元的27.0%.1952年以来,由于人口增加的持续压力和环境政策的原因,中国陆地生态系统服务价值和净价值持续减少;1998年以后,中国政府陆续实施了一系列森林保护政策,中国陆地生态系统服务价值和净价值止跌回稳.但相关政策忽略了林地以外其他生态系统的保护,导致农田、湿地和草地等生态系统严重退化.由于社会经济条件、资源禀赋差异,不同地区之间的生态服务价值和净价值差异显著.为了维护生态平衡,生态修复(尤其是人工生态修复)和社会经济发展都应该注重成本效益问题,通过不同措施的成本收益比较,最大限度地降低生态保护项目的成本,增加环境保护项目的收益,这是修复生态学需要面对的重要科学问题.

关键词：生态服务成本分析环境保护土地管理生态修复

Using optical coherence tomography images to evaluate fungal growth in reline resins

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journal of Innovative Optical health sciences 2023年第3期16卷 113-123页

作者： Mayra M.Aquino caio b.s.Maior Nathália A.E.lins cláudia c.b.O.Mota Patricia l.A.Nascimento 3nderson s.l.Gomes Graduate Program in Dentistry Universidade Federal de Pernambuco(UFPE)Recife Brazil center of Risk Analysis Reliability Engineering and Environmental Modeling Universidade Federal de Pernambuco(UFPE)Recife Brazil Faculty of Dentistry centro Universitario Tabosa de Almeida(AscEs)caruaru Brazil Department of Physics Universidade Federal de Pernambuco(UFPE)Recife Brazil

As changes in hard or soft oral tissues normally have a microbiological component,it is important to develop diagnostic techniques that support clinical evaluation,without destroying microbio-logical *** optical coherence tomography(OcT)represents an alternative to analyze tissues and microorganisms without the need for *** imaging technique could be defined as a fast,real-time,in situ,and non-destructive ***,this study proposed the use of the OcT to visualize biofilm by candida albicans in reline resins for removable *** reline resins(silagum-comfort,coe comfort,and soft-confort),with distinct char-acteristics related to wa ter sorption and fungal inhibition were used.A total of 30 samples(10 for each resin group)were subjected to OcT scanning before and 96 h after inoculation with candida albicans(URM 6547).The biofilm analysis was carried out through a 2D optical callisto sD-OcT(930 nm)operated in the spectral ***,the images were preprocessed using a3×3 Gaussian filter to remove the noise,and then Otsu binarization,allowing segmentation and pixel *** layer's biofilm formed was clearly defined and,indeed,its visualization is modified by water sorption of each ***-comfort and *** showed some similarities in the scattering of light between the clean and inoculated samples,in which,the latter samples presented higher values of light signal ***-comfort samples were the only ones that showed no di®erences between the clean or inoculated ***,the results of this study suggest that OcT is a viable technique to visualize the biolm in reline *** in the literature are still scarcely using the OcT technique to visualize biolm in reline resins,further studies are *** should not contain any references or displayed equations.

关键词： OcT reline resin biofilm removable prosthesis.

WETTAbIlITY bETWEEN Tib_2 cERAMIc AND METAls

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Acta Metallurgica sinica(English letters) 1999年第4期12卷 395-400页

作者： j.Y. Zhang, Z.Y. Fu , W.M Wang , h. Wang and x.M. Min state key lab .of Advanced Technologyfor Materials synthesis and Processing, Wuhan University of Technolo gy, Wuhan 430070 ,china

self consistent Field discrete variational xα( scF xα DV) method was used to study the wettabilitybetween Tib2 ceramic and Metals. The Metals were Ni, Mo, Ni+ Mo, and etc. microstructureof Tib2/ Fe, Tib2/ Niand Tib2/ NiMoinvestigatedby TEM werechosen toidentify the calculation model. The result shows the wetting in the above systems were chemicalreactive wetting ,and can becalculated by scF xα DV . Theeffectof active ele ment( Mo) to Tib2/ Ni wettability wasstudied too.

关键词： wetting scF xα DV ceramic/ metalcomposite( cMc)

high heat Flux Tests of small-scale be/cu Mock-ups for ITER

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Southwestern Institute of Physics Annual Report

southwestern Institute of Physics Annual Report 2006年第1期 180-181页

作者： lIU xiang ZhANG Fu chEN jiming ZhANG Nianmang PAN chuanhong WANG x. s. ZhANG P. c. WANG Z.h. WANG l. WAN Z. j. TAN Y.M . WU jihong xU Zengyu 不详 National key laboratory for surface Physics and chemistry China Academy of Engineering Physics Mianyang China Ningxia Orient Non-ferrous Metals Group co. ltd Shizuishan City Ningxia China Nuclear Power Institute of china P. O. Box 436 Chengdu 610041 China

high temperature hIP joining technology of be/cucrZr alloy or Ds-cu has been applied by Europe and japan for the frabrication of ITER first wall. At the first stage of our research, high temperature hIP joining of be/cucrZr alloy was investigated by referencing their successful experience and Ti was selected as interlayer. since the first wall will receive high heat flux during ITER operation, the heat load resistance capabilities, in particular thermal fatigue property is a crucial criterion of FW mock-ups. In order to test the heat load resistance capabilities of be/cucrZr joints, an electron beam heat load facility with beryllium handling capability has been constructed and heat removal performances and thermal cycling tests of be/cucrZr joints were carried out.

关键词：铍铜高温处理热循环

The combined effects of grain and sample sizes on the mechanical properties and fracture modes of gold microwires

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journal of Materials science & Technology 2019年第1期35卷 76-83页

作者： h.K.Yang K.cao Y.han M.Wen j.M.Guo Z.l.Tan j.lu Y.lu hong Kong branch of National Precious Metals Material Engineering Research center City University of Hong Kong Department of Mechanical and biomedical Engineering City University of Hong Kong state key laboratory of Advanced Technologies for comprehensive Utilization of Platinum Metals Sino-platinum Metals Co.Ltd center for Advanced structural Materials City University of Hong Kong Shenzhen Research Institute

hall-Petch relation was widely applied to evaluate the grain size effect on mechanical properties of metallic material. however, the sample size effect on the hall-Petch relation was always ignored. In the present study, the mechanical test and microstructure observation were performed to investigate the combined effects of grain and sample sizes on the deformation behaviors of gold microwires. The polycrystalline gold microwires with diameter of 16 ?m were annealed at temperatures from 100°c to 600°c, leading to different ratios(t/d) of wire diameter(t) to grain size(d) from 0.9 to 16.7. When the t/d was lower than 10, the yield stress dropped fast and deviated from the hall-Petch relation. The free-surface grains played key role in the yield stress softening, and the volume fraction of free-surface grains increased with the t/d decreasing. Furthermore, the effects of t/d on work-hardening behaviors and fracture modes were also studied. With t/d value decreasing from 17 to 3.4, the samples exhibited necking fracture and the dislocation pile-ups induced work-hardening stage was gradually *** the t/d value further decreasing(t/d he fracture mode turned into shear failure, and the work-hardening capability lost. As the gold microwire for wire bonding is commonly applied in the packaging of integrated circuit chips, and the fabrication of microwire suffers multi-pass cold-drawing and annealing treatments to control the grain size. The present study could provide instructive suggestion for gold microwire fabrication and bonding processes.

关键词： Gold microwire Wire bonding Tensile testing Grain size hall-Petch relationship

An ecological model with the p-laplacian and diffusion

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International journal of biomathematics 2016年第1期9卷 157-163页

作者： s. h. Rasouli Department of Mathematics Faculty of Basic Sciences Babol University of Technology Babol Iran

We study the existence of positive solutions of a population model with diffusion of the form {-△pu=aup-1-f（u）-c/ua,x∈Ω,u=0,x∈Ω where △p denotes the p-laplacian operator defined by △pz =div（｜z｜P-2z）, p 〉 1, Ω is a bounded domain of RN with smooth boundary, α∈ c （0, 1）, a and e are positive constants. here f ： [0, ∞） → R is a continuous function. This model arises in the studies of population biology of one species with u representing the concentration of the species. We discuss the existence of positive solution when f satisfies certain additional conditions. We use the method of sub- and super-solutions to establish our results.

关键词： Ecological model infinite semipositone sub- and super-solutions.

涂布法制备三明治式的曲安奈德口腔膜剂及其体外释放行为的研究

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中国药学杂志 2024年第9期59卷 801-808页

作者：张莉莉陈艺黄静刘丽娜汤磊王建塔贵州医科大学药学院贵阳550004 贵州省化学合成药物研发利用工程技术研究中心贵州医科大学贵阳550004

目的制备一种由背衬层、缓释层和黏附层组成的载曲安奈德的“三明治”式口腔膜剂用于治疗口腔溃疡。方法以乙基纤维素、羟丙基甲基纤维素和聚丙烯酸为载体,采用涂布法制备曲安奈德口腔膜剂。以膜剂外观、厚度、均匀度和黏附性、机械强... 详细信息

目的制备一种由背衬层、缓释层和黏附层组成的载曲安奈德的“三明治”式口腔膜剂用于治疗口腔溃疡。方法以乙基纤维素、羟丙基甲基纤维素和聚丙烯酸为载体,采用涂布法制备曲安奈德口腔膜剂。以膜剂外观、厚度、均匀度和黏附性、机械强度等为指标,通过单因素法优化背衬层、缓释层和黏附层处方。以市售制剂Taisho®为对照,对该膜剂的理化性质和体外药物释放进行评估。结果制得曲安奈德三层口腔膜剂载药量为96.0%,该膜剂具有较好的均一性、机械强度和黏附性,与市售制剂Taisho®的释放行为对比,两者的相似因子f2为54.25。结论采用涂布法制备的曲安奈德口腔膜剂与Taisho®有较好的质量一致性。该膜剂的制备工艺简单可行,具有一定的产业化优势。

关键词：曲安奈德三层口腔膜剂缓释黏膜黏附涂布法

Weighted Oscillation and Variation Inequalities for singular Integrals and commutators satisfying hrmander Type conditions

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Acta Mathematica sinica,English series 2017年第10期33卷 1397-1420页

作者： jing ZhANG huo xiong WU school of Mathematics and statistics Yili Normal College Yining 835000 P. R. China school of Mathematical sciences Xiamen University Xiamen 361005 P. R. China

This paper is devoted to investigating the weighted lP-mapping properties of oscillation and variation operators related to the families of singular integrals and their commutators in higher dimension. We establish the weighted type （p, p） estimates for 1 〈 p 〈 ∞ and the weighted weak type （1, 1） estimate for the oscillation and variation operators of singular integrals with kernels satisfying certain hsrmander type conditions, which contain the Riesz transforms, singular integrals with more general homogeneous kernels satisfying the lipschitz conditions and the classical Dini＇s conditions as model examples. Meanwhile, we also obtain the weighted lP-boundeness for such operators associated to the family of commutators generated by the singular integrals above with bMO（Rd）-functions.

关键词： Oscillation variation singular integrals commutators bMO functions hsrmander con-ditions Muckenhoupt weights

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烷基酚聚氧乙烯醚磷酸酯的合成及性能评价

广州化工 2024年第6期52卷 49-52页

作者：柯耀斌赵建华南充职业技术学院四川南充637000 西南石油大学新能源与材料学院四川南充637000

随着人们环保意识的增加,烷基酚聚氧乙烯醚磷酸酯作为一种用途广泛、对环境友好的新型表面活性剂得到了大众的青睐。本文以壬基酚聚氧乙烯醚、多聚磷酸为原料合成烷基酚聚氧乙烯醚磷酸酯APEP-4,用IR光谱对产物的结构进行表征。研究了不... 详细信息

随着人们环保意识的增加,烷基酚聚氧乙烯醚磷酸酯作为一种用途广泛、对环境友好的新型表面活性剂得到了大众的青睐。本文以壬基酚聚氧乙烯醚、多聚磷酸为原料合成烷基酚聚氧乙烯醚磷酸酯APEP-4,用IR光谱对产物的结构进行表征。研究了不同温度、不同原料配比和反应时间对酯化反应的影响,最佳反应条件为:温度90℃、n(聚磷酸)∶n(NP-4)=1.2、反应时间4 h。酯化率位90.1%,单酯含量占比82.7%。并计算了最优实验合成条件下的样品的hlb_(Abc)=8.3,属于亲油性,可用作与润湿剂。对合成产物做耐碱性、漂洗性和气泡性进行了测定。

关键词： NP-4(壬基酚聚氧乙烯醚) 多聚磷酸条件优化性能测定