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台风路径的可预报性——第一部分:澳大利亚地区的热带气旋

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气象科技 1990年第2期18卷 19-27页

作者： k. Fraedrich L. m. Leslie 陆曼云澳大利亚气象局研究中心

用非线性系统分析的方法,研究了1959-1980年澳大利亚热带地区249个热带气旋的路径(取样时间间隔为6小时).首先对热带气旋路径的混沌度或不规则特性作了估计.混沌度是通过先将全部热带气旋路径标准化到一个共同起始位置,然后测量初始位... 详细信息

用非线性系统分析的方法,研究了1959-1980年澳大利亚热带地区249个热带气旋的路径(取样时间间隔为6小时).首先对热带气旋路径的混沌度或不规则特性作了估计.混沌度是通过先将全部热带气旋路径标准化到一个共同起始位置,然后测量初始位置相近的一对对热带气旋路径的平均偏离(速)率的方法来估计的.通过热带气旋路径的相关积分的计算,发现相应的动力学过程的维数在6到8之间,e倍误差增长时间尺度约为1天.本文研究结果表明直到24小时的澳大利亚地区热带气旋移动的预报是确定性的预报.超过这一时限,则需要认真考虑以统计为基础的方法.澳大利亚热带气旋位置方差的实际观测值与在平均漂移上迭加随机移动模式预报值比较的结果证实了上述结论.对应的两者很接近,在18-24小时以后,经验的和理论的热带气旋预报的位置方差呈线性地增长,表明随机模式在超过24小时的预报方面所起的作用.

关键词：热带气旋可预报性台风路径随机移动起始位置非线性系统随机模式预报值确定性系统时间尺度

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制备奥托金的几种可供选择的方法

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火炸药 1982年第5期 55-63+52页

作者： V.L.Siele m.Warman J.Leccacorvi R.W.Hutchinson R.motto e.e.Gilbeit T.m.Benzinger m.D.Coburn R.k.Rohwer R.k.Davey 孙姣花陈正衡美国洛斯·阿拉莫斯科学实验室煤炭工业部煤炭工业部美国陆军武器研究发展指挥部美国陆军武器研究发展指挥部美国陆军武器研究发展指挥部美国陆军武器研究发展指挥部美国陆军武器研究发展指挥部美国陆军武器研究发展指挥部美国洛斯·阿拉莫斯科学实验室美国洛斯·阿拉莫斯科学实验室美国洛斯·阿拉莫斯科学实验室

本文叙述三种由乌洛托品制备奥托金(HmX)的新方法,每种方法都是先进行乙酰化然后再硝化,其中以DADN为中间产物的方法的HmX得率,比目前以乌洛托品和醋酐为基础的Bachmann法要高,但要采用后者不必采用的硫酸和聚磷酸。已经表明,DADN可在... 详细信息

本文叙述三种由乌洛托品制备奥托金(HmX)的新方法,每种方法都是先进行乙酰化然后再硝化,其中以DADN为中间产物的方法的HmX得率,比目前以乌洛托品和醋酐为基础的Bachmann法要高,但要采用后者不必采用的硫酸和聚磷酸。已经表明,DADN可在中间规模以良好的得率快速连续地生产,废酸回收也没有什么问题。

关键词：五氧化二磷五氧化二氮氧化氮硝酸氮化合物氮杂环辛烷 HmX 聚磷酸 DAPT 氮杂环己烷哌啶乌洛托品托金

Numerical modelling of flow and transport in rough fractures

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Journal of Rock mechanics and Geotechnical engineering 2014年第6期6卷 535-545页

作者： Scott Briggs Bryan W.karney Brent e.Sleep University of Toronto Toronto M5S 1A4 Canada

Simulation of flow and transport through rough walled rock fractures is investigated using the latticeBoltzmann method （LBm） and random walk （RW）, respectively. The numerical implementation isdeveloped and validated on general purpose graphic processing units （GPGPUs）. Both the LBm and RWmethod are well suited to parallel implementation on GPGPUs because they require only next-neighbourcommunication and thus can reduce expenses. The LBm model is an order of magnitude faster onGPGPUs than published results for LBm simulations run on modern CPUs. The fluid model is verified forparallel plate flow, backward facing step and single fracture flow; and the RWmodel is verified for pointsourcediffusion, Taylor-Aris dispersion and breakthrough behaviour in a single fracture. Both algorithmsplace limitations on the discrete displacement of fluid or particle transport per time step to minimise thenumerical error that must be considered during implementation. 2014 Institute of Rock and Soil mechanics, Chinese Academy of Sciences. Production and hosting byelsevier B.V. All rights reserved.

关键词： Hydrogeology Fracture flow Solute transport Computational fluid dynamics Lattice Boltzmann method(LBm) Random walk(RW)

Natural Contaminants in Drinking Waters (Arsenic, Boron, Fluorine and Vanadium) in the Southern Pampean Plain, Argentina

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Journal of environmental Protection 2011年第1期2卷 97-108页

作者： martín e. espósito Juan D. Paoloni mario e. Sequeira Nilda m. Amiotti maría del C. Blanco 不详

This research aims at making a diagnosis of the presence of arsenic, boron, fluorine and vanadium in the waters from the basin of el Divisorio stream, tributary of Paso de las Piedras reservoir, in the southwest of Buenos Aires Province. This storage is used to provide water to the cities of Bahía Blanca and Punta Alta with a population of approximately 400,000 inhabitants. A selective and specific sampling of wells, perforations and superficial watercourses was made in 46 points, in an area of nearly 400 km2. Groundwaters had arsenic (max. 0.114 mg/l) exceeding the reference guideline in 97.3% of the samples, boron (max. 1.42 mg/l), vanadium (max. 0.8 mg/l) and fluorine (max. 6.6 mg/l), being respect- tively, 91.9%, 82.9%, and 67.6%. Regarding the superficial flow, while arsenic concentrations were higher than the limit in 100% of the cases (max. 0.072 mg/l), 88.9% corresponded to elevated boron (max. 1 mg/l) and vanadium (max. 0.23 mg/l) and only 22.2% to fluorine (max. 3.18 mg/l) ones. In all these cases, concentrations exceed the reference guideline values suggested by the World Health Organization, the Argentine Food Code and the environmental Protec- tion Agency. The presence of these contaminants that finally could determine the quality of the water resource entering the reservoir is attributed to the natural characteristics of the environment since contributions by anthropic actions have not been detected in the area. The most critical sectors in the basin were identified in order to stress the possible negative influence of consuming these waters on the community’s health, with the purpose of reporting the results to institutions, authorities and the population and applying them to preventive medicine.

关键词： Arsenic Fluorine Vanadium Hydrochemistry Risk

Chitosan/Nanocrystalline Cellulose Biocomposites Based on Date Palm (Phoenix Dactylifera L.) Sheath Fibers

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Journal of Renewable materials 2019年第6期7卷 567-582页

作者： Abeer m.Adel Amira m.el-Shafei Atef A.Ibrahim mona T.Al-Shemy Cellulose and Paper Department National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt Textile Research Division National Research Center33El-Bohouth St.(Former El-Tahrir St.)DokkiP.O.12622GizaEgypt

In this study,nanocrystalline celluloses were used to enhance physical,mechanical and water vapor barrier properties of chitosan films for potential food packaging *** different mineral acids(sulfuric and phosphoric)were used to extract nanocrystalline cellulose from date palm sheath *** influence of cellulose I and cellulose II on the properties of the isolated nanocrystalline celluloses(e.g.,yield,energy and length of intra-and intermolecular hydrogen bonds,and degree of substitution)were studied *** characteristics of chitosan biocomposite film with phosphorylated nanocrystalline cellulose were compared to those with sulfated nanocrystalline *** showed that besides cellulose polymorphism,the ionic ester groups on the surface of nanocrystalline cellulose is one of the factors influencing the physical,chemical,mechanical,and water vapor barrier properties in chitosan/nanocrystalline cellulose biocomposites.

关键词： Biocomposite Cellulose I Cellulose II Nanocrystalline cellulose(NCC) physico-mechanical properties Thermal stability

白介素1A基因多态性增加了阿尔茨海默病患者颅内小神经胶质细胞活性

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世界核心医学期刊文摘（神经病学分册） 2005年第2期1卷 41-42页

作者： Hayes A. Green e.k. Pritchard A. Prof. D.m.A. mann 郭俊 Neuroscience Research Group University of Manchester Hope Hospital Manchester M6 8HD United Kingdom

Objective: To investigate the impact of possession of the -889 C/T polymorphi sm of the interleukin 1A gene (IL-1A) and the -511 C/T polymorphism of the int erleukin 1B gene (IL-1B) on the extent of neuroinflammation in the brain in Alz heimers disease (AD), as demonstrated by the degree of microglial cell activit y associated with each IL-1A and IL-1B genotype. method: microglial cell activ ity within the frontal cortex was determined in 68 patients with necropsy confir med AD by image analysis as the percentage area of tissue occupied by ferritin i mmunostained material (microglial cell load). IL-1A, IL-1B, and apolipoprotein e (APOe) genotyping were performed by polymerase chain reaction on DNA extracte d from frontal cortex or cerebellum. Results: The microglial cell load was 31%g reater in patients with IL-1A T allele, 62%greater with IL1A TT genotype, but 108%greater with IL-1A TT genotype in combination with APOe 4 allele. No effec ts on microglial cell load occurred with polymorphisms in IL-1B, or APOe alone. Conclusions: Polymorphisms within IL-1A influence the degree of brain microgli al cell activation, especially in bearers of APOe 4 allele, reinforcing the impo rtance of neuroinflammatory processes in the pathogenesis of AD, and supporting the rationale for treating the disease with inflammation modulating drugs.

关键词：阿尔茨海默病神经胶质细胞基因多态性内小额叶皮质载脂蛋白颅内神经免疫染色炎症程度聚合酶链反应

Organic Amendments Improve Plant morpho-Physiology and Antioxidant metabolism in mitigating Drought Stress in Bread Wheat(Triticum aestivum L.)

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Phyton-International Journal of experimental Botany 2022年第9期91卷 1959-1972页

作者： Taufika Islam Anee md.Nur Nabi Islam mohamed m.Hassan Abdul Awal Chowdhury masud md.mahabub Alam mirza Hasanuzzaman Department of Agronomy Faculty of AgricultureSher-e-Bangla Agricultural UniversityDhaka1207Bangladesh Department of Biology College of ScienceTaif UniversityTaif21944Saudi Arabia

Due to the unpredictable climate change,drought stress is being considered as one of the major threats to crop ***(Triticum aestivum *** Gom-26)being a dry season crop frequently faces scarcity of water and results in a lower ***,this experiment aims to explore the role of different organic amendments(OAs)in mitigating drought stress-induced *** pot experiment consisted of different organic amendments ***,vermicompost and poultry manure@0.09 kg m^(−2)soil,biochar@2.5%w/w soil and chitosan@1%w/w soil which was imposed on the plants grown under both well-watered and drought *** showed that drought stress reduced plant height(15%),SPAD value(16%),relative water content(13%),number of spikelet spike^(−1)(17%),number of grains spike^(−1)(12%),and 100-grain weight(18%).Organic amendments act as a protectant and reduce drought stress-induced damages by enhancing the morpho-physiological and yield *** enhanced SPAD value by 18%,number of spikelets spike^(−1)by 20%,number of grains spike^(−1)by 17%,whereas poultry manure increased plant height by 16%under drought condition compared to control *** other OAs applied,vermicompost was proved to be capable of reducing the higher lipid peroxidation and proline content raised by drought *** stress-induced increment of catalase,ascorbate peroxidase and glutathione reductase activities were also efficiently modulated by the organic amendment *** present study concluded that OAs play significant roles in alleviating drought stressinduced damages by improving the morpho-physiological attributes and among the different types of OAs used vermicompost performed better which in addition ceased the production of reactive oxygen species.

关键词： Antioxidant defense biochar cereal crop chitosan compost poultry manure reactive oxygen species vermicompost

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冷冻治疗光化性角化病的前瞻性研究

世界核心医学期刊文摘（皮肤病学分册） 2005年第2期1卷 42-43页

作者： Thai k.-e. Fergin P. Freeman m. P. Foley 崔荣 Department of medicine Dermatology The University of Melbourne St. Vincent's Hospital Melbourne PO Box 2900 Fitzroy Vic. 3065 Australia Dr.

Background. Actinic keratoses are the most common actinic lesions on Caucasian skin. Cryosurgery with liquid nitrogen is commonly used to treat actinic keratoses, but there have been few studies examining the true rate of cure in everyday dermatologic practice. Aim. To determine prospectively the true efficacy of cryosurgery as a treatment for actinic keratoses in everyday dermatologic practice. methods. A prospective, multicentered study (a subsidiary study of a photodynamic therapy trial) was performed. Patients with untreated actinic keratoses greater than 5 mm in diameter on the face and scalp were recruited. eligible lesions received a single freeze-thaw cycle with liquid nitrogen given via a spray device and were reviewed 3 months thereafter. each center used their preferred freeze time. The only treatment criterion was complete freezing of actinic keratoses and a 1-mm rim of normal *** lesions were assessed as complete response or noncomplete response. The influence of the duration of freeze, cosmetic outcomes, and adverse events were examined. Results. Ninety adult patients from the community with 421 eligbe actinic keratoses were recruited. The overall individual complete response rate was 67.2%[Sem = ±3.5%; 95%confidence interval (CI = 60.4-74.1%]. Complete response was 39%for freeze times of less than 5 s, 69%for freeze times greater than 5 s, and 83%for freeze times greater than 20 s. Cosmetic outcomes were good to excellent in 94%of complete response lesions. The main adverse events were pair, stinging, and burning during treatment, and hypopigmentation after healing. Conclusions. Closuqery is an effective treatment for actinic keratoses. The true complete response rate is significantly lower than that previously reported. The freeze duration influences. successful treatment. Adverse events are mild and well tolerated.

关键词：光化性角化病冷冻治疗液氮冷冻治疗仪面部皮损冷冻时间成人患者多中心性喷射式持续时间

Optimization of mortar Compressive Strength Prepared with Waste Glass Aggregate and Coir Fiber Addition Using Response Surface methodology

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Journal of Renewable materials 2023年第10期11卷 3751-3767页

作者： Cut Rahmawati Lia Handayani muhtadin muhammad Faisal muhammad Zardi S.m.Sapuan Agung efriyo Hadi Jawad Ahmad Haytham F.Isleem Department of Civil engineering Universitas AbulyatamaAceh Besar23372Indonesia Advanced engineering materials and Nano Technology Research Center Universitas AbulyatamaAceh Besar23372Indonesia Faculty of Fisheries Universitas AbulyatamaAceh Besar23372Indonesia Department of mechanical engineering Universitas AbulyatamaAceh Besar23372Indonesia Advanced engineering materials and Composites Research Center(AemC) Department of Mechanical and Manufacturing EngineeringUniversiti Putra MalaysiaSelangor43400Malaysia Department of mechanical engineering Universitas MalahayatiLampung35153Indonesia Department of Civil engineering Millitary College of EngineeringRisalpur24080Pakistan Department of Construction management Qujing Normal UniversityQujing655011China

Waste Glass(WGs)and Coir Fiber(CF)are not widely utilized,even though their silica and cellulose content can be used to create construction *** study aimed to optimize mortar compressive strength using Response Surface methodology(RSm).The Central Composite Design(CCD)was applied to determine the optimization of WGs and CF addition to the mortar compressive *** strength and microstructure testing with Scanning electron microscope(Sem),Fourier-transform Infrared Spectroscopy(FT-IR),and X-Ray Diffraction(XRD)were conducted to specify the mechanical ability and bonding between the matrix,CF,and *** results showed that the chemical treatment of CF produced 49.15%cellulose,with an average particle size of 1521μ*** regression of a second-order polynomial model yielded an optimum composition consisting of 12.776%WGs and 2.344%CF with a predicted compressive strength of 19.1023 mPa.C-S-H gels were identified in the mortars due to the dissolving of SiO_(2) in WGs and *** silica from WGs increased the C-S-H *** plays a role in preventing,bridging,and branching micro-cracks before reaching maximum *** aggregates and chemically treated CF are suitable to be composited in mortar to increase compressive strength.

关键词： Cellulose response surface methodology waste glass coir fiber composite