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Effects of atmospheric circulation on summertime precipitation variability and glacier mass balance over the Tuyuksu Glacier in Tianshan Mountains, Kazakhstan

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Journal of Arid Land 2015年第5期7卷 687-695页

作者： nina K kononova nina V PIMANKINA Lyudmila A YERISKOVSKAYA LI Jing BAO Weijia LIU Shiyin Institute of Geography Russian Academy of Sciences Institute of Geography Ministry of Education and Science State Key Laboratory of Cryospheric Sciences Cold and Arid Regions Environmental and Engineering Research InstituteChinese Academy of Sciences

The amount and the form of precipitation have significant effects on glacier mass balances in high al- titude mountain areas by controlling the accumulation, the ablation and the energy balance of a glacier through impact on the surface albedo. The liquid precipitation has negative effects on glacier accumulation and may in- crease the ablation of surface ice through the heat input for melting. The timing and the forms of precipitation over glacierized regions depend on the weather processes both locally and regionally. Early studies showed that regional to large-scale atmospheric circulation processes play a key role in affecting the precipitation events over glaciers. This paper analyzed the relationship between the inter-annual variability of the summertime precipitation over the Tuyuksu Glacier and the atmospheric circulation types, which related to various atmospheric circulation types in the Northern Hemisphere. Results indicated that the decrease in the duration of zonal processes and the increase in the meridional northern processes were observed in the last decade. The total summer precipitation associated with these processes also increased along with an increase of summertime solid precipitation. Although the decadal fluctuation of glaciological parameters were found in dependent of the above large-scale atmospheric circulation processes, global warming was a dominant factor leading to the mass loss in the recent decades under the back- ground of the increase in precipitation over the Tuyuksu Glacier.

关键词： atmospheric circulation precipitation glacier mass balance

Permutation orbifolds of vertex operator superalgebras and associative algebras

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Science China Mathematics 2025年第1期 19-38页

作者： Chongying Dong Feng Xu nina Yu Department of Mathematics University of California at Santa Cruz Department of Mathematics Huzhou University Department of Mathematics University of California at Riverside School of Mathematical Sciences Xiamen University

Let V be a vertex operator superalgebra and g =（1 2 ···k） be a k-cycle which is viewed as an automorphism of the tensor product vertex operator superalgebra V■*** this paper,we construct an explicit isomorphism from Ag(V■k) to A（V） if k is odd and to Aσ（V） if k is even where σ is the canonical automorphism of V of order 2 determined by the superspace structure of *** recover previous results by Barron（2016）and Barron and Vander Werf（2014） that there is a one-to-one correspondence between irreducible g-twisted V■k-modules and irreducible V-modules（*** σ-twisted V-modules） when k is odd（***）.This explicit isomorphism is expected to be useful in our further study on the Zhu algebra of the fixed point subalgebra.

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Seismic loss assessment of RC high-rise buildings designed according to Eurocode 8

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Earthquake Engineering and Engineering Vibration 2023年第3期22卷 807-824页

作者： Jelena Pejovic nina Serdar Faculty of Civil Engineering University of MontenegroBulevar Dzordza Vasingtona bbPodgorica 81000Montenegro

A probabilistic seismic loss assessment of RC high-rise(RCHR)buildings designed according to Eurocode 8 and located in the Southern Euro-Mediterranean zone is presented *** loss assessment methodology is based on a comprehensive simulation approach which takes into account ground motion(GM)uncertainty,and the random effects in seismic demand,as well as in predicting the damage states(DSs).The methodology is implemented on three RCHR buildings of 20-story,30-story and 40-story with a core wall structural *** loss functions described by a cumulative lognormal probability distribution are obtained for two intensity levels for a large set of simulations(NLTHAs)based on 60 GM records with a wide range of magnitude(M),distance to source(R)and different site soil conditions(SS).The losses expressed in percent of building replacement cost for RCHR buildings are *** the estimation of losses,both structural(S)and nonstructural(NS)damage for four DSs are *** effect of different GM characteristics(M,R and SS)on the obtained losses are ***,the estimated performance of the RCHR buildings are checked to ensure that they fulfill limit state requirements according to Eurocode 8.

关键词： RC high-rise buildings seismic loss assessment loss functions nonlinear time-history analysis(NLTHA) cumulative lognormal probability distribution random effects Eurocode 8

Study on electronic density topology of various cluster models of Mg/Al hydrotalcite by density functional theory

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Journal of Natural Gas Chemistry 2010年第2期19卷 179-184页

作者： Renqing Lu nina Zhang College of Chemistry and Chemical Engineering China University of Petroleum （East China） Qingdao 266555 Shandong China

The geometry and electronic topology properties of Mg/Al hydrotalcite cluster models were comparatively investigated by means of density functional theory at GGA/DND *** results suggested that cluster model containing seven octahedral cations was the smallest size to be employed to simulate other *** fact that the n＋ charge of cluster models containing n aluminum atoms can reflect electronic properties of anionic clay layer *** bond lengths of clusters can be modified by terminating with or without OH-/H2O groups in terms of principle of bond order conservation.

关键词： hydrotalcite density functional theory cluster model Mg/Al

Immersion graded index optics:theory,design,and prototypes

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Microsystems & Nanoengineering 2022年第3期8卷 235-245页

作者： nina Vaidya lav Solgard Electrical Engineering Stanford UniversityStanfordCA 94305USA Faculty of Eengineering and Physical Sciences Universty of SouthamptonSouthampton SO167QFUK

Immersion optics enable creation of systems with improved optical concentration and coupling by taking advantage of the fact that the luminance of light is proportional to the square of the refractive index in a lossless optical *** graded index optical concentrators,that do not need to track the source,are described in terms of theory,simulations,and *** introduce a generalized design guide equation which follows the Pareto function and can be used to create various immersion graded index optics depending on the application requirements of concentration,refractive index,height,and *** present glass and polymer fabrication techniques for creating broadband transparent graded index materials with large refractive index ranges,(refractive index ratio)^(2)of~2,going many fold beyond what is seen in nature or the optics *** prototypes demonstrate 3x optical concentration with over 90%*** report via functional prototypes that graded-index-lens concentrators perform close to the theoretical maximum limit and we introduce simple,inexpensive,design-flexible,and scalable fabrication techniques for their implementation.

关键词： graded optics refractive

3D printed optics with nanometer scale surface roughness

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Microsystems & Nanoengineering 2018年第1期4卷 255-262页

作者： nina Vaidya Olav Solgaard Electrical Engineering Stanford University348 Via Pueblo MallStanfordCA 94305-4090USA

Complex optical devices including aspherical focusing mirrors,solar concentrator arrays,and immersion lenses were 3D printed using commercial technology and experimentally demonstrated by evaluating surface roughness and *** as-printed surfaces had surface roughness on the order of tens of *** improve this unacceptable surface quality for creating optics,a polymer smoothing technique was *** force microscopy and optical profilometry showed that the smoothing technique reduced the surface roughness to a few nanometers,consistent with the requirements of high-quality optics,while tests of optical functionality demonstrated that the overall shapes were maintained so that near theoretically predicted operation was *** optical surface smoothing technique is a promising approach towards using 3D printing as a flexible tool for prototyping and fabrication of miniaturized high-quality optics.

关键词： optics roughness smoothing

A MULTI-OBJECTIVE ROBUST OPERATION MODEL FOR ELECTRONIC MARKET ENABLED SUPPLY CHAIN WITH UNCERTAIN DEMANDS

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Journal of Systems Science and Systems Engineering 2007年第1期16卷 74-87页

作者： Jiawang XU Xiaoyuan HUANG nina YAN Management Department Shenyang Institute of Aeronautical Engineering Shenyang 110136 China School of Business Administration Northeastern University Shenyang 110004 China

A multi-objective robust operation model is proposed in this paper for an electronic market enablexi supply chain consisting of multi-supplier and multi-customer with uncertain demands. Suppliers in this supply chain provide many kinds of products to different customers directly or through electronic market. Uncertain demands are described as a scenario set with certain probability;, the supply chain operation model is constructed by using the robust optimization method based on scenario analyses. The operation model we proposed is a multi-objective programming problem satisfying several conflict objectives, such as meeting the demands of all customers, minimizing the system cost, the availabilities of suppliers＇ capacities not below a certain level, and robustness of decision to uncertain demands. The results of numerical examples proved that the solution of the model is most conservative; however, it can ensure the robustness of the operation of the supply chain effectively.

关键词： Operation management robust optimization objective programming electronic market

Spectrophotometric study of the charge transfer complexes of 4′-nitrobenzo-15-crown-5 and benzo-15-crown-5 with iodine in nonaqueous solvents

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Chinese Chemical Letters 2011年第5期22卷 587-590页

作者： nina Alizadeh Sadegh Dehghanikhah Department of Chemistry Faculty of ScienceUniversity of GuilanRashtIran

The formation of charge transfer complex between iodine with 4＇-nitrobenzo-15-crown-5（NB15C5） and benzo-15-crown-5 （B15C5） is investigated spectrophotometrically in chloroform and dichloromethane（DCM） solutions at 25℃.The pseudo-first-order rate constants for the transformation process were evaluated from the absorbance-time data and found to vary in the order of DCM CHCl_*** values of the formation constant,K_f,for each complex are evaluated from Benesi-Hilebrand equation. Stability of the resulting complex in two solvents was also found to vary in the order of DCM CHCl_3.

关键词： Charge transfer complex Spectrophotometry Kinetic Crown ether

Understorey species distinguish late successional and ancient forests after decades of minimum human intervention: A case study from Slovenia

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Forest Ecosystems 2023年第1期10卷 92-101页

作者： Mirjana Sipek Tim Ravnjak nina Sajna University of Maribor Faculty of Natural Sciences and MathematicsKoroska c.1602000MariborSlovenia

The main species composition drivers in temperate deciduous forests are environmental conditions, a stand?s age and the site history, e.g., the succession stage and past land use, as well as disturbance regime and current management. We compared plant species diversity and composition in late successional and ancient forests, cooccurring on the same small river island applying species accumulation curves and nonmetric multidimensional scaling, respectively. Given the island?s geomorphological characteristics, we expected these to be very similar before human intervention in the past. The forests experienced differing disturbance regimes in the past, while over the last 30 years, human intervention has been the same and reduced to a minimum. The ancient forest in this study had two major characteristics defining it as old, mature forest: continuity of presence for more than 200years and specific composition. The late successional forest experienced major disturbance in the 20th century and was allowed natural regeneration by bordering on the ancient forest, representing a potential species pool,and by decades of minimum human intervention. Our results showed that, even though there was no difference in species richness, we could still detect differences between the forests, particularly in the abundance and species composition of the understorey, among which geophytes had the most indicative importance. To make our results useful on a broader scale, we composed from the literature a species list of plants indicative for ancient forest and tested its application. These results are important for distinguishing between old and mature secondary stands and particularly for identifying old forest stands, which should be conserved and, in the case of fragmented landscapes, included in a network connecting forest fragments.

关键词： Forest community Successional forest Indicator plants Plant diversity Understorey Geophytes