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Topographic and lithologic controls behind mountain depopulation in Zlatibor District(Western Serbia)

Journal of Mountain Science 2020年第2期17卷 271-288页

作者： TELBISZ Tamas BRANKOV Jovana CaliC Jelena Department of Physical Geography Eotvos Loránd UniversityBudopestHungary Geographical Institute"Jovan Cvijic"of the Serbian Academy of Sciences and Arts BelgradeSerbia South Ural State University Institute of SportsTourism and Service60Sony Krivoy streetChelyabinsk454080Russia

Mountain depopulation is a worldwide phenomenon observed in all continents. It has varied socio-economic reasons;among others, the low profitability of traditional agriculture, the better job possibilities and the higher level of services in urban settlements. However, it is often recognized that depopulation is related to natural factors such as elevation, slope or lithology. It is also observed that protected areas are frequently established in depopulated mountain regions. Their primary aim is the conservation of nature, but they may help tourism development as well. Tourism, in turn, may slow down or even reverse the process of depopulation. In this study, we investigate the impact of topographic and lithologic factors, namely of karst settings, on mountain demographic processes and the relationship of protected areas and tourism through the example of the northern part of Zlatibor District(Western Serbia). The study area is characterized by mountains and hills at elevations from 200 to 1600 m a.s.l. Our aim is to find GIS-based statistical relationships between topographic, lithologic factors and demographic characteristics. In this area, mountain depopulation started after WWII, and weproved that this process was strongly controlled by topographic factors. The higher and more dissected the area, the more significant is the decrease of the population and the more advanced is the ageing. As a result, population density contrasts are much more pronounced now than 70 years ago. After WWII, depopulation and ageing became gradually more serious on karstic terrains than on non-karst. However, by using compound topographic and lithologic types, we proved that it is not the effect of karst, but the effect of topography. The flow of population from hills and mountains to valleys and basins are closely related to the restructuring of the economic sectors. At present, for the study area, the development of tourism is unequivocally naturebased and connected to protected ar

关键词： Depopulation Ageing National park Tara Mountain Tourism Rural Population density

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巴基斯坦政府门户网站公众初始接受的影响因素研究——基于使用意向和执行意向双重视角

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情报学报 2019年第5期38卷 543-556页

作者： Irfan ali Shah 王芳南开大学商学院信息资源管理系天津300071 南开大学网络社会治理研究中心天津300071

目前巴基斯坦政府网站的公众使用还处于起步阶段。提高政府门户网站的公众初始接受度,是巴基斯坦政府发展电子政务、提高公信力、打造便民政府的关键举措,探索公众对政府网站初始采纳的影响因素具有重要意义。本研究从使用意向和执行意... 详细信息

目前巴基斯坦政府网站的公众使用还处于起步阶段。提高政府门户网站的公众初始接受度,是巴基斯坦政府发展电子政务、提高公信力、打造便民政府的关键举措,探索公众对政府网站初始采纳的影响因素具有重要意义。本研究从使用意向和执行意向双重视角重新审视传统的技术接受模型。研究结果表明,执行意向在实际行为形成过程中发挥显著的直接效应,同时通过中介效应提升使用意向对实际行为的解释力;情景线索对于执行意向具有显著正向作用。研究结果对于巴基斯坦深化政府电子政务服务、建设服务型政府网站具有理论指导意义,同时也在理论上深化了政府网站采纳的理论研究。

关键词：政府网站使用意向执行意向中介作用

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Biomass and nutrients allocation in pot cultured beech seedlings:influence of nitrogen fertilizer

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Journal of Forestry Research 2008年第4期19卷 263-270页

作者： ali Bagherzadeh Rainer Brumme Friedrich Beese Institute of Agriculture Azad University of Mashhad Institute of Soil Science and Forest Nutrition Georg-August-University of Goettingen

Allocation of biomass and nutrient elements including Nitrogen to above and belowground compartments of beech seedlings （Fagus sylvatica L.） treated by labeled nitrogen fertilizer in the form of 15NH4 and 15NO3 were investigated at the end of two successive growing seasons. Pot cultured beech seedlings were grown at a green house on intact soil cores sampled from three adjacent stands including beech, Norway spruce and mixed beech-spruce cultures of Soiling forest, Germany. Comparing biomass allocation and nutrients concentrations of the seedlings between the control and 15N-fertilized treatments revealed no significant effect of N fertilization on nutrients uptake by seedlings over the experiment. The form of N input influenced its movement into plant pools. It was demonstrated that beech seedlings take up nitrogen mainly in the form of nitrate, which is then reduced in the leaves, although the differences between the retention of NO3^--N and NH4^＋-N in plants were not statistically significant. Percent recoveries of 15N in trees were typically greater after 15NO3 than after 15NH4 additions. It was indicated that immobilization of ~SN tracer in fine roots was a slower process comparing other plant compartments such as stem and coarse roots, but a powerful sink for N during the course of study.

关键词： beech seedling nitrogen fertilizer biomass nitrogen immobilization nutrient mycorrhiza

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CeTrivium:A Stream Cipher Based on Cellular Automata for Securing Real-Time Multimedia Transmission

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Computer Systems Science & Engineering 2023年第12期47卷 2895-2920页

作者： Osama S.Younes Abdulmohsen Alharbi ali Yasseen Faisal Alshareef Faisal Albalawi Umar A.Albalawi Faculty of Computer and Information Technology University of TabukTabuk71491Saudi Arabia Faculty of Computers and Information Menoufia UniversityMenoufia13829Egypt School of Computing&Data Science Wentworth Institute of TechnologyBoston02115USA

Due to their significant correlation and redundancy,conventional block cipher cryptosystems are not efficient in encryptingmultimedia *** based onCellularAutomata(CA)can provide amore effective *** CA have recently gained recognition as a robust cryptographic primitive,being used as pseudorandom number generators in hash functions,block ciphers and stream *** have the ability to perform parallel transformations,resulting in high throughput ***,they exhibit a natural tendency to resist fault *** stream cipher schemes based on CA have been proposed in the ***,their encryption/decryption throughput is relatively low,which makes them unsuitable formultimedia *** and Grain are efficient stream ciphers that were selected as finalists in the eSTREAM project,but they have proven to be vulnerable to differential fault *** work introduces a novel and scalable stream cipher named CeTrivium,whose design is based on *** is a 5-neighborhood CA-based streamcipher inspired by the designs of Trivium and *** is constructed using three building blocks:the Trivium(Tr)block,the Nonlinear-CA(NCA)block,and the Nonlinear Mixing(NM)*** NCA block is a 64-bit nonlinear hybrid 5-neighborhood CA,while the Tr block has the same structure as the Trivium stream *** NM block is a nonlinear,balanced,and reversible Boolean function that mixes the outputs of the Tr and NCA blocks to produce a *** of CeTrivium has indicated that it can resist various attacks,including correlation,algebraic,fault,cube,Meier and Staffelbach,and side channel ***,the scheme is evaluated using histogramand spectrogramanalysis,aswell as several differentmeasurements,including the correlation coefficient,number of samples change rate,signal-to-noise ratio,entropy,and peak signal-to-noise *** performance of CeTrivium is evaluated and compared with other state-of-

关键词： Stream ciphers cellular automata securing real-time streaming cryptography CeTrivium

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Fiber-reinforced composites in milling and grinding:machining bottlenecks and advanced strategies

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Frontiers of Mechanical Engineering 2022年第2期17卷 1-35页

作者： Teng GAO Yanbin ZHANG Changhe LI Yiqi WANG Yun CHEN Qinglong AN Song ZHANG Hao Nan LI Huajun CAO Hafiz Muhammad ali Zongming ZHOU Shubham SHARMA School of Mechanical and Automotive Engineering Qingdao University of TechnologyQingdao 266520China School of Mechanical Engineering Dalian University of TechnologyDalian 116024China Chengdu Tool Research Institute Co. Ltd.Chengdu 610500China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China School of Mechanical Engineering Shandong UniversityJinan 250061China School of Aerospace University of Nottingham Ningbo ChinaNingbo 315100China School of Mechanical Engineering Chongqing UniversityChongqing 400044China Mechanical Engineering Department King Fahd University of Petroleum and MineralsDhahran 31261Saudi Arabia Hanergy(Qingdao)Lubrication Technology Co. Ltd.Qingdao 266100China Department of Mechanical Engineering IK Gujral Punjab Technical UniversityPunjab 144603India

Fiber-reinforced composites have become the preferred material in the fields of aviation and aerospace because of their high-strength performance in unit *** composite components are manufactured by near netshape and only require finishing operations to achieve final dimensional and assembly *** and grinding arise as the preferred choices because of their precision ***,given their laminated,anisotropic,and heterogeneous nature,these materials are considered *** undesirable results and challenging breakthroughs,the surface damage and integrity of these materials is a research hotspot with important engineering *** review summarizes an up-to-date progress of the damage formation mechanisms and suppression strategies in milling and grinding for the fiber-reinforced composites reported in the ***,the formation mechanisms of milling damage,including delamination,burr,and tear,are ***,the grinding mechanisms,covering material removal mechanism,thermal mechanical behavior,surface integrity,and damage,are ***,suppression strategies are reviewed systematically from the aspects of advanced cutting tools and technologies,including ultrasonic vibration-assisted machining,cryogenic cooling,minimum quantity lubrication(MQL),and tool optimization *** vibration shows the greatest advantage of restraining machining force,which can be reduced by approximately 60%compared with conventional *** cooling is the most effective method to reduce temperature with a maximum reduction of approximately 60%.MQL shows its advantages in terms of reducing friction coefficient,force,temperature,and tool ***,research gaps and future exploration directions are prospected,giving researchers opportunity to deepen specific aspects and explore new area for achieving high precision surface machining of fiber-reinforced composites.

关键词： milling grinding fiber-reinforced composites damage formation mechanism delamination material removal mechanism surface integrity minimum quantity lubrication

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Temperature dependence of nitrogen mineralization and microbial status in O_H horizon of a temperate forest ecosystem

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Journal of Forestry Research 2008年第1期19卷 37-43页

作者： ali Bagherzadeh Rainer Brumme Friedrich Beese Department of Agriculture Azad University of MashhadEmamyeh Boulevard Institute of Soil Science and Forest Nutrition Georg-August-University of GoettingenBuesgenweg 237077 GoettingenGermany

It was hypothesized that increasing air and/or soil temperature would increase rates of microbial processes including litter decomposition and net N mineralization, resulting in greater sequestration of carbon and nitrogen in humus, and consequently development in OH horizon （humus horizon）. To quantify the effect of temperature on biochemical processes controlling the rate of OH layer development three adjacent forest floors under beech, Norway spruce and mixed species stands were investigated at Soiling forest, Germany by an incubation experiment of OH layer for three months. Comparing the fitted curves for temperature sensitivity of OH layers in relation to net N mineralization revealed positive correlation across all sites. For the whole data set of all stands, a Q10 （temperature sensitivity index） value of 2.35-2.44 dependent on the measured units was found to be adequate for describing the temperature dependency of net N mineralization at experimental site. Species-specific differences of substrate quality did not result in changes in biochemical properties of OH horizon of the forest floors. Temperature elevation increased net N mineralization without significant changes in microbial status in the range of I to 15℃. A low Cmic /Corg （microbial carbon/organic carbon） ratio at 20℃ indicated that the resource availability for decomposers has been restricted as reflected in significant decrease of microbial biomass.

关键词： beech spruce nitrogen mineralization forest floor temperature temperature sensitivity index (Q10)

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CENTENNIAL CPC ACHIEVES MIRACLES IN CHINA,BOOSTS WORLD HARMONY,SAYS PAKISTANI EXPERT

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Good Neighbours 2022年第1期 54-55页

作者： ali Jaswal Jiang Chao Xinhua reporters

Since its founding 10o years ago,the Communist Party of China(CPC)has led China to achieve fast and remarkable socio-economic progress,a wonder of the human society,a Pakistani expert has *** reasons behind these accomplishments are the CPC's people-centered policies and its accurate grasp of the pulse of the times,Fazal Ur Rahman,director of Pakistan Institute of China Studies at the University of Sargodha told Xinhua in a recent interview.

关键词：中国研究中心经济奇迹始终坚持拉赫曼巴基斯坦奉献精神时代前列人民至上

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Oxygen-doped Carbon Nitride Nanocages with Efficient Photon-to-Electron Conversion for Selective Oxidation of Xylose/Xylan to Yield Xylonic Acid

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Paper And Biomaterials 2023年第2期8卷 53-65页

作者： Junqiang Zhang Zhuoyan Xie Zulfiqar ali Ning Li Qimeng Liu Wenyue Fan Jiliang Ma Runcang Sun Liaoning Key Lab of Lignocellulose Chemistry and BioMaterials Liaoning Collaborative Innovation Center for Lignocellulosic BiorefineryCollege of Light Industry and Chemical EngineeringDalian Polytechnic UniversityDalianLiaoning Province116034China

Highly efficient photon-to-electron conversion is crucial for achieving photocatalytic *** this study,oxygen-doped carbon nitride nanocages(O@CNNCs)were engineered via dual strategies of morphology-controlled heteroatom doping,which was successfully used in the photocatalytic selective oxidation of xylose/xylan to xylonic *** nanocage-shaped O@CNNCs had a larger surface area,which was 4.02 times of carbon nitride(CN).Furthermore,with the assistance of morphology regulation and O-doping,O@CNNCs exhibit highly efficient photon-to-electron conversion,enhanced visible-light utilization,high photocurrent,low resistance,and fast separation/migration of electron-hole ***,the photocatalytic oxidation of xylose to xylonic acid using O@CNNCs was successfully achieved under mild reaction conditions with a yield of 83.4%.O@CNNCs have excellent recyclability,in which the yield of xylonic acid in the 5th cycle was 98.2%of its initial *** O@CNNC photocatalytic system was also suitable for macromolecular xylan,and a xylonic acid yield of 77.34 mg was obtained when 100 mg xylan was *** oxidation-active species captured experiments indicated that holes were crucial for the selective oxidation of xylose to xylonic ***,this study provides a new strategy for the preparation of photocatalysts with excellent photon-to-electron conversion and selective oxidation of biomass-derived feedstocks to xylonic acid.

关键词： photon-to-electron conversion morphology regulation oxygen doping selective oxidation xylonic acid

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碱蓬内生真菌曲霉TQ67次级代谢产物的研究

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中国药学杂志 2018年第7期53卷 504-507页

作者：吴斌 Sayed Asmat ali Shah 陶倩楠浙江大学海洋学院浙江舟山316021

目的研究植物碱蓬内生真菌曲霉TQ67次级代谢产物。方法采用ODS反相柱色谱、高效液相色谱、半制备HPLC等方法对发酵液及菌丝体部分分离纯化,运用核磁、质谱等现代波谱分析方法对化合物进行结构鉴定。结果得到8个化合物:aspermutarubrol(1... 详细信息

目的研究植物碱蓬内生真菌曲霉TQ67次级代谢产物。方法采用ODS反相柱色谱、高效液相色谱、半制备HPLC等方法对发酵液及菌丝体部分分离纯化,运用核磁、质谱等现代波谱分析方法对化合物进行结构鉴定。结果得到8个化合物:aspermutarubrol(1)、sydowiols D(2)、sydowiols E(3)、细交链孢酮酸(4)、(E)-5-(羟甲基)-2-(6'-甲基-2'-庚烯-2'-基)酚(5)、sydonol(6)、(7S)-(+)-7-O-methylsydonol(7)和hydroxysydonic acid(8)。化合物2/3和化合物1其DPPH的IC_(50)分别为(9.79±0.33)和(32.30±1.02)μg·mL^(-1),FRAP值分别为(230.55±2.50)和(278.99±8.32)μg·mL^(-1)。结论从碱蓬内生真菌曲霉TQ67中分离得到的化合物2/3和化合物1有较强的抗氧化活性。

关键词：碱蓬内生真菌次生代谢产物抗氧化

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Temperature dependence of carbon mineralization and nitrous oxide emission in a temperate forest ecosystem

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Journal of Forestry Research 2008年第2期19卷 107-112页

作者： ali Bagherzadeh Rainer Brumme Friedrich Beese Department of Agriculture Azad University of Mashhad Emamyeh Boulevard P.O Box: 91735-413 Mashhad Iran Institute of Soil Science and Forest Nutrition Georg-August-University of Goettingen Buesgenweg 2 37077 Goettingen Germany

The measurement of CO2 and N2O effiux from forest soils is of great importance in evaluating the role of forests as sequestering agents of atmospheric CO2 and nitrogen. To quantify the effect of site on temperature dependence of net C-mineralization and N2O-N emissions, three adjacent forest floors under beech, Norway spruce and mixed species stands were investigated at Soiling forest, Germany, by an incubation experiment for three months. The investigated net C-mineralization and N2O-N emissions from all forest floors exhibited an exponential increase with respect to temperature elevation. The temperature coefficient function （Q10 value）, was fitted to flux rates to describe the temperature sensitivity of forest floors on temperature in the range of 1-20℃. Comparing the fitted curves for temperature sensitivity of the forest floors in relation to net carbon mineralization and nitrous oxide emission rates revealed a strong positive correlation across all sites. For the whole data set of all stands, a Q10 value of 1.73-2.10 for net C-mineralization and 2.81-3.58 for N2O-N emissions per measured unit was found to describe the temperature dependency of net C-mineralization and N20-N efflux at experimental site. The absence of clear differences between beech and spruce in mono and mixed species cultures on temperature dependencies of net C-mineralization and N2O-N emission rates indicated that the flux rates were not affected by species-specific differences of litter quality.

关键词： beech spruce net C-mineralization nitrous oxide emission temperature temperature sensitivity index (Q10)

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