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Tropical Cyclone Research and Review 2014年第2期3卷 78-90页

作者： JEFF CALLAGHAN KEVIN TORY Bureau of Meteorology Queensland Offi ceBrisbaneAustralia Centre for Australian Weather and Climate Research MelbourneAustralia

The Brisbane Tropical Cyclone Warning Centre has used two forms of a thermal advection diagnostic to identify relatively large areas of isentropic ascent and descent for many years. When the thermodynamic conditions are favourable the ascent regions are correlated with significant outbreaks of convection that produce heavy rainfall. The diagnostic is based on the relationship between geostrophic winds that turn with height and flow perpendicular to thickness contours. As the relationship is also valid for the more general case of gradient winds, the diagnostic, in theory, should be useful for most heavy-rain-bearing tropical systems. A climatology of rainfall rate with one form of the diagnostic is presented at two Queensland locations(one tropical and one subtropical) that demonstrates a clear relationship between the isentropic ascent wind distribution and heavy to extreme rainfall.The diagnostics applied to numerical weather prediction models are valuable forecast tools as they identify heavy rainfall threat regions within which the extreme rain is likely to fall, whereas the rainfall from the same models is often under predicted or has large location errors. Applied to tropical lows and tropical cyclones the diagnostics have been used successfully to forecast tropical cyclone formation and rapid intensification and decay. Examples of such intensification and decay from around the world are presented, as well as a climatology of the diagnostic applied to intensifying tropical cyclones in the Australian region.

关键词： shear thermal advection intensifi cation rainfall isentropic ascent

REAL-TIME FORECASTS OF TYPHOON RAPID INTENSIFIcation IN THE NORTH WESTERN PACIFIC BASIN WITH THE NCEP OPERATIONAL HWRF MODEL

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Tropical Cyclone Research and Review 2014年第2期3卷 63-77页

作者： VIJAY TALLAPRAGADA CHANH KIEU Environmental Modeling Center NOAA/NWS/NCEPCollege ParkMarylandU.S.A I.M.Systems Group RockvilleMarylandU.S.A

This study presents the real-time performance of the United States(US) National Centers for Environmental Prediction(NCEP) operational Hurricane Weather Research and Forecast(HWRF) model in predicting rapid intensification(RI) of typhoons in the North Western Pacific(WPAC) basin in 2013. Examination of all RI cases in WPAC during 2013 shows that the HWRF model captures a consistent vortex structure at the onset of all RI as seen in previous idealized studies with HWRF. However, HWRF has issues with predicting RI when the model vortex is initialized with intensity greater than hurricane strength. Further verification of the probability of detection(POD) and the false alarm rate(FAR) of RI forecasts shows that the HWRF model outperforms all other models used by the US Navy’s Joint Typhoon Warning Center, possessing highest POD and lowest FAR in 2013. Examination of the intensity change forecasts at different forecast lead times also confirms that the HWRF model has superior performance, particularly at the 72-h lead time with the POD index ~0.91 and the FAR index ~0.33. Such unique performance of the HWRF model demonstrates its role in helping operational agencies improve their official intensity(and RI) forecasts for tropical cyclones in the WPAC basin.

关键词： rapid intensifi cation typhoons/tropical cyclones operational forecasting

Coronary Calcium Scoring in 2017

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Cardiovascular Innovations and Applications 2016年第B12期2卷 101-110页

作者： Kazuhiro Osawa Rine Nakanishi Matthew Budoff Los Angeles Biomedical Research Institute at Harbor University of California-Los Angeles Los AngelesCAUSA

Coronary artery calcifi cation(CAC)is as an independent risk predictor of cardiovascular disease and can classify an individual’s risk of atherosclerotic cardiovascular disease,particularly in intermediate-risk individuals.Also,CAC progression is associated with greater rates of cardiovascular events.This article provides available data and expert recommendations for CAC based on current publications.We focus on the utility of CAC for stratifi cation of individuals and describe its diagnostic value in identifying patients at risk.We also describe the important ability of CAC to derisk a patient with a score of zero.

关键词： coronary artery calcifi cation ASCVD risk

DIABATIC HEATING AND CONVECTIVE ASYMMETRIES DURING RAPID INTENSITY CHANGES OF TROPICAL CYCLONES OVER NORTH INDIAN OCEAN

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Tropical Cyclone Research and Review 2016年第1期5卷 32-46页

作者： B.GEETHA S.BALACHRAN India Meteorological Department Regional Meteorological Centre

Rapid changes in Tropical Cyclone(TC)structure and intensity are the most diffi cult aspects of TC forecasting.The intensity and structural changes associated with rapid intensifi cation(RI)and rapid weakening(RW)instances of TCs of North Indian Ocean(NIO)are analysed based on 5 cases each for RI and RW.The vertical profi les of heat(Q_1)and moisture(Q_2)based on heat and moisture budget equations are analysed to bring out the role of diabatic heating during the RI and RW processes.The associated structural changes are analysed based on the Fourier fi rst order wave number-1 asymmetry in the precipitation patterns associated with RI and RW instances.During RI process,there are 2 predominant Q_1 maxima associated with latent heat release near the TC centre,one in the upper troposphere and the other in the lower troposphere.During RW process,there is a single dominant Q_1 and Q_2 maxima in the mid-troposphere.Regarding the structural changes,there is a pronounced front-back asymmetry in both RI and RW cases.The asymmetry amplitude in the inner core is lower in the case of RI events but,is quite high for RW events.Thus,RW events are characterised by large convective asymmetry.

关键词： tropical cyclone rapid intensifi cation heat budget moisture budget rainfall asymmetry Fourier analysis

OPERATIONAL TROPICAL CYCLONE FORECAST VERIFIcation PRACTICE IN THE WESTERN NORTH PACIFIC REGION

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Tropical Cyclone Research and Review 2012年第3期1卷 361-372页

作者： HUI YU SAI TICK CHAN BARBARA BROWN MASASHI KUNITSUGU EDWARD FUKADA SANGWOOK PARK WOOJEONG LEE YINGLONG XU PEOU PHALLA BOUNTEUMSYSOUPHANTHAVONG SAU WA CHANG CHE GAYAH ISMAIL RENITO BPACIENTE PATRICIA EE CHAMNONG KAEOCHADA HOA VO VAN Laboratory of Typhoon Forecast Technique Shanghai Typhoon InstituteChina MeteorologicalAdministrationShanghaiChina Hong Kong Observatory Hong KongChina National Center for Atmospheric Research BoulderU.S.A. Japan Meteorological Agency TokyoJapan Joint Typhoon Warning Center HawaiiU.S.A. National Typhoon Centre Korea Meteorological AdministrationJejuR.O.K. National Meteorological Centre China Meteorological AdministrationBeijingChina Department of Meteorology Phnom PenhCambodia Department of Meteorology and Hydrology of Lao PDR VientianeLao P.D.R. Macao Meteorological and Geophysical Bureau MacaoChina Malaysian Meteorological Department SelangorMalaysia Philippine Atmospheric Geophysical and Astronomical ServicesQuezon CityPhilippines Meteorological Service Singapore Singapore Thai Meteorological Department BangkokThailand National Hydro-Meteorological Services of Vietnam HanoiVietnam

This paper summarizes results of a survey of the operational status of tropical cyclone(TC) forecast verifi-cation in the western North Pacific region, covering the Members of the ESCAP/WMO Typhoon Committee, RSMC Tokyo-Typhoon Center, and JTWC. Results of the survey indicate that significant efforts have been focused on the verification of TC forecast guidance by operational forecast agencies in the region, either individually or through international cooperation. A variety of TC forecast verification products are available to the forecasters in either real time or in post-season through multiple means, with the main focus on the deterministic track and intensity forecasts. Only a few verification products are available for probabilistic forecasts. Verification of TC precipitation and high wind forecasts are also lacking sufficient attention in the region. It would be helpful in the future to focus more attention toward these aspects and incorporate methods that will provide a greater depth of information regarding the TC forecast performance.

关键词： Tropical cyclone forecast verifi cation

Mitral Stenosis:A Review

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Cardiovascular Innovations and Applications 2018年第B1期2卷 459-465页

作者： C.Richard Conti Department of Medicine University of FloridaGainsevilleFLUSA

Mitral stenosis due to rheumatic heart disease is not common in the United States but is common in the developing world because rheumatic fever is still occurring frequently.Symptoms usually gradually occur in the young adult(most commonly female).Atrial fibrillation is a common accompanying rhythm in patients with proven mitral stenosis.The main physiologic event is a pressure gradient between the left atrium and the left ventricle.Diagnosis is relatively straight forward using physical exam and simple laboratory studies such as Chest X-Ray(elevated Left main stem bronchus,Double Density indicating enlarged left atrium)and ECG(P-Mitrale).Cardiac ultrasound confirms the clinical diagnosis(Doming of mitral valve in diastole,Hockey stick deformity of the anterior mitral valve leaflet,large left atrium,Doppler estimation of valve gradient).Mitral commisurotomy(surgical or Balloon)is warranted if the valve is pliable and not heavily calcified.

关键词： rheumatic fever mitral annular calcifi cation cardiac output cardiac ultrasound

Three-Center Configuration with Four,Three, and Two Electrons for Carbon,Boron, Hydrogen, and Halogen Exchange. A Model and Theoretical Study with Experimental Evidence

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Open Journal of Physical Chemistry 2014年第2期4卷 33-43页

作者： Henk M. Buck Kasteel Twikkelerf 94 Tilburg The Netherlands

The introduction of specific sites in organic frames for accommodation of various modes of bonding has been focused on reaction types which are described by using different theoretical models with or without a definite experimental proof. In this study three-center four-, three-, and two-electron systems based on carbon-, boron-, hydrogen-, and halogen exchange are under consideration. Based on the number of electrons in the transition state or transition complex it is shown that all transfer or exchange reactions share the same ratio numbers expressed as the quotient of the transitional bond distance under investigation and its normal bond length. With X-ray data of model systems it was even possible to give the ratio numbers for a three-center four-electron configuration experimental support with additional ab initio data. Furthermore a novel model type of substitution in organic chemistry is introduced through electrophilic insertion, informative for enzyme-substrate interactions based on the lock-and-key model. Reactions based on a three-center two-electron configuration mostly follow a nonlinear transition. In this alignment there will be a pursuit of cyclization for stabilization via homoaromaticity as homocyclopropenyl cation. The molecular dynamics of such a process is discussed based on recent X-ray crystallographic data of the symmetrically bridged, nonclassical geometry of the 2-norbornyl cation. In the present paper the focus is aimed at the transition intermediate of the (classical) 2-norbornyl cation involved in the isomerization into the nonclassical geometry. This model description is compared with a simple molecular rearrangement of the 1-propyl cation into the corner-protonated cyclopropane using the ab initio data. The exclusivity of the former isomerization compared with the latter one could be unambiguously demonstrated by the invention that theintramolecularelectron shift can be expressed in a linear relationship between the concerned electron-donating and accepting bond lengths. Finally, th

关键词： Three-Center Configuration Frozen Transition State Molecular Drone Enigma Classical and Nonclassical 2-Norbornyl cation

Effect of Hydrochloric Acid on the Structural of Sodic-Bentonite Clay

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Journal of Minerals and Materials Characterization and Engineering 2014年第5期2卷 404-413页

作者： Samira Bendou Moussa Amrani Laboratory of Soft Technology Recovering and Sustainable Development Faculty of Science M’Hamed Bougara University Boumerdes Algeria

The objective of this work is to determine changes of surface properties of a bentonite after acid activation, using hydrochloric acid solutions (HCl) at room temperature. XRD, FX, FTIR, MEB, and BET analyses of the samples have been carried out to examine the structure of bentonite before and after acid activation. It is found that the raw bentonite is composed of dioctahedral montmorillonite with predominant quantity and certain amounts of quartz, albite and illite, etc. It has an cation exchange capacity (CEC) of 74.32 meq/g which allows it to be characterized as typical sodium bentonite. The changes, at low acid concentrations, are the result from from cation exchange (exchangeable cations with H+ ions). Differences of surface area at high acid concentrations (0.25 - 0.4 M) were caused by structural changes and partial decomposition of the samples. Data of surface area measurements have showed that with increase of concentration of hydrochloric acid, the surface area increased. The maximum value (837.11 m2/g) was reached by the sample activated with 0.4 M HCl. By against, activation with higher concentration (0.6 M) caused a decrease in the surface area.

关键词： Bentonite Sodic-Montmorillonite Acid Activation cation Exchange Capacity Surface Area

Development of Performance Models for Boiler Feed Water Treatment Ion Exchange Facility

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Advances in Chemical Engineering and Science 2018年第4期8卷 280-297页

作者： Kenneth Kekpugile Dagde Department of Chemical Petrochemical Engineering Rivers State University Port Harcourt Nigeria

The treatments of raw water using resins embedded with cation and anion were investigated in this study via a developed mathematical model. The developed mathematical model was used to predict the amount of sodium (Na+), calcium (Ca2+), magnesium (Mg2+) and ammonium (NH4+ ) ions removed by the resin embedded with hydrogen ion (H+) in the cation bed. The model was also used to investigate the amount of chloride (Cl-) and sulphate (SO42- ) ions treated by the resin embedded with hydroxyl ion (OH-) in the anion bed. The effect of flow rate and superficial velocity were also investigated. The simulation results showed that there was significant reduction of Na+, Ca2+, Mg2+, , Cl- and SO4 2-from their initial concentrations in raw water. This showed that the mathematical model was able to predict the concentrations of cations and anions investigated in this study. The result revealed that the flow rate of water has effect on the treatment of cations and anions in raw water using ion-exchange resins. Thus, operating the resin beds at very high flow rate reduced its performance while at very low flow rate the residence time of wastewater on the bed increased with resultant increase in performance. Similarly, high superficial velocity reduced the amount of ion concentration removed by the resin in both beds. The total final concentrations of cations in the cation bed by the model were 0.0003156, 0.0003452 and 0.0036 mol/m3 at 4.0, 4.5 and 6.5 m/min respectively while that from the anion bed were 0.0002597, 0.0002769 and 0.00205 mol/m3 at 4.0, 4.5 and 6.5 m/min respectively. The predicted model results, when compared with the maximum allowable limit of total concentration of both cations and anions of a functional industrial company (Notore chemical), showed a maximum percentage deviation ranging from 2.00% to 3.53%. This showed that the developed model has achieved its set objectives.

关键词： Raw Water cation Anion Ion Exchange Mathematical Modeling

Alkali Fusion Synthesis of Zeolitic Materials from Waste Dehydrated Cake Discharged from Recycling of Construction Waste Soil

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Natural Resources 2017年第4期8卷 300-305页

作者： Takaaki Wajima Department of Urban Environment Systems Chiba University Chiba Japan

An inorganic cation exchanger, zeolitic material, was synthesized from dehydrated cake, which was discharged from recycling of construction waste soil, using the alkali fusion method. The waste clay was mixed with NaOH powder (the weight ratio of NaOH/waste clay = 1.0) and then heated at 300°C for 1 h to make a fused material. This fused material was then added to distilled water, and then heated at 90°C, 120°C, 150°C and 180°C for 12 h in reaction bombs under autogenous pressure in order to synthesize the cation exchanger. As a result, waste cake can be converted into fused material with high solubility, and zeolitic materials can be synthesized from the fused material. A mixture of zeolite-X and hydroxysodalite was synthesized at 90°C and 120°C, hydroxysodalite alone was synthesized at 150°C and 180°C. By increasing the synthesis temperature, the cation exchange capacity (CEC) of the product decreased, and the highest CEC of the product at 90°C, including zeolite-X, was 2.06 mmol/g, which is 64.3% of commercial zeolite-13X (3.2 mmol/g).

关键词： Waste Clay Alkali Fusion Zeolite-X Hydroxysodalite cation Exchange Capacity