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Observations of NO_2 and O_3 during Thunderstorm Activity using Visible Spectroscopy

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Advances in Atmospheric Sciences 1996年第3期13卷 359-374页

作者： D.b.Jadhav A.L.Londhe S.bose Indian Institute of Tropical Meteorology Dr.Homi Bhabha MargPashanPune-411008MaharashtraIndiaIndian Institute of Tropical MeteorologyDr.Homi Bhabha MargPashanPune-411008MaharashtraIndiaIndian Institute of Tropical MeteorologyDr.Homi Bhabha MargPashanPune-411008MaharashtraIndia

Simultaneous observations for the total column densities of NO2,O3 and H2O were carried on using the portable Spectrometer (438-450 nm and 400-450 nm) and the visible Spectrometer (544.4-628 nm) during premonsoon thunderstorms and embedded hail storm activity at Pune (18°32'N & 73°51'E),*** observations confirm the fact that there is an increase in O3 and NO2 column densities during *** increase in O3 was observed following onset of thunderstorm,while the increase in NO2 was observed only after the thunder flashes *** implies that the production mechanisms for O3 and NO2 in thunderstorm are *** observed column density of NO,value (1 to 3×1017molecules cm-2) during thunderstorm activity is 10 to 30 times higher than the value (1×10th molecules cm-2) of a normal day total column *** spectrometric observations and observations of thunder flashes by electric field meter showed that 6.4×1025molecules/flash of NO2 are *** increased to-oil column density of ozone during thunderstorm period is 1.2 times higher than normal (clear) day ozone *** multiple scattering in the clouds is estimated from H2O and O2 absorption bands in the visible spectral region Considering this effect the calculated amount of ozone added in the global atmosphere due to thunderstorm activity is 0.26 to 0 52 Du,and the annual production of ozone due to thunderstorm activity is of the order of 4.02×10 molecules/year The annual NO2 production may be of the order of 2.02×1035molecules/year.

关键词： Visible Spectroscopy Thunderstorm Ozone production NO2 production Atmospheric electricity Lightning flashes. Multiple scattering factor

A MODIFIED HEAT CONDuCTION MODEL

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Chinese Journal of Mechanical Engineering 1995年第3期8卷 175-186页

作者： Harry Gingold Dinesh Gera(Department of Mathematics)( Department of Mechanical &Aerospace Engineering)West Virginia university(Morgantown WV 26506 u.S.A)

The purpose of this paper is to devise a new model of heat conduction for a body which istotally insulated at its boundary. The essence of the new model is modification of the Fourier law insuch a way that the resulting heat conduction problem will be fonnulated as an initial value problemwith a nonstandard partial differential equation. The values of normal derivatives of the heat fiuxto various orders for all tmies (t> 0) will be detemined by the governing partial differential equa-tion and the values of normal derivatives of fluxes at the initial time (t=0). We study the properitesof this model and demonstrate its validity for a simple onedimensional case of a thin bar insulatedat both ends.

关键词： Heatconduction Model

Intensification of the degradation of Acid RED-18 using hydrodynamic cavitation

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Emerging Contaminants 2020年第1期6卷 20-32页

作者： Prashant b.Dhanke Sameer M.Wagh Chemical Engineering Department Padmabhooshan Vasanraodada Patil Institute of Technology BudhgaonSangliMH416304India Chemical Technology Department Laxminarayan Institute of TechnologyNagpurMH440033India

In this work degradation of Acid Red-18(AR-18)was examined in the hydrodynamic cavitation *** plates with different holes geometry are used to determine the optimum plate to carry out the degradation based on cavitation *** obtained optimum orifice plate is used as a cavitating device on varying parameters like initial AR-18 concentrations,pH,temperatures,and operating pressures of the reactor.A photocatalyst(TiO2)was prepared by the sol-gel method and used in combination with H2O2 to intensify the degradation of *** obtained optimum condition of hydrodynamic cavitation was again used in the ultrasonic cavitation reactor for the *** cavitation(orifice)given the highest degradation as compared to Hydrodynamic cavitation(Venturi)and ultrasonic Cavitation with and without the use of *** TiO2(300 mg/L)dose,88.1%,70.4%and 64.8%degradation is obtained in HC-O,HC-V and uC reactor at initial AR-18 concentration(15 ppm),pH(3),Operating temperature(35C),and H2O2(300 mg/L).Hence the use of an advanced oxidation process can be successfully used with hydrodynamic cavitation to intensify the degradation of Acid Red-18 under the controlled operating parameters.

关键词： Acid Red-18 Hydrodynamic cavitation Hydrogen peroxide Photocatalyst Advance oxidation

Consumption Pattern of Carotene Rich Foods and Development of a Year Calendar

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biomedical and Environmental Sciences 1996年第2期9卷 212-222页

作者： DEVADAS RAJAMMAL,P. CHANDRASEKHAR,u. PREMAKuMARI S. AND SAISHREE, R.(Avinashilingam Institute for Home Science and Higher Education for Women, Deemed university, Coimbatore 641 043, India) Avinashilingam Institute for Home Science and Higher Education for Women Deemed University Coimbatore India

Consumption pattern of beta carotene rich foods from 500 households of Coimbatore district was elicited. Through market surveys in four seasons namely: summer, south-west monsoon, north-east monsoon and winter, a year calendar of beta carotene rich foods was developed. The total and beta carotene contents of five commonly consumed beta carotene rich foods both in raw and cooked states were determined. Results indicated that greens were mainly purchased from market and consumed 2-3 times per week. Cooking loss was maximum in boiling and minimum in shallow fat frying. Curry leaves (Murraya koenigii),amaranth tender (Amaranthus gangeticus), agathi (Sesbania grandopra), and ponnanganni (Alternanthera sessilis) were the carotene rich foods available round the year. Cost of most greens was highest in summer and lowest in north-east monsoon. Within a cost of 13-14 ps in summer, 4-10 ps in south-west monsoon and north-west monsoon and 4-12 ps in winter season, the entire day's requirement of beta carotene (2400μg) could be obtained in the form of agathi/amaranth throughout the year: in the form of drumstick leaves and mint in south-west monsoon; as curry leaves and coriander leaves in winter and as agathi,paruppukeerai and amaranth in summer. From this year calendar, according to seasonal availability and cost, low-cost high carotene foods can be selected and used for increasing the beta carotene intake in the intervention programmes and in the community

关键词： Rich Consumption Pattern of Carotene Rich Foods and Development of a Year Calendar

Freeze-thaw Resistance of Concrete in Seawater

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武汉理工大学学报 2010年第17期32卷 108-111页

作者： SHuI Z H Xu H G ZHAN b J School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Transportation bureau of Xinganmeng Inner Mongolia Ulanhot 137400China

The effect of freeze-thaw cycles in seawater on the performance of concrete was studied in this paper. Concrete samples with different water binder ratio and different component were prepared,and were then put into fresh water and synthesized seawater. After the experiments of freeze-thaw cycles,the mass loss,relative dynamic elastic modulus (RDEM) and compressive strength of each sample were tested. The results obtained reveal that with the increase of the water binder ratio,the resistance ability of freeze-thaw impact in seawater of concrete decrease dramatically. When the concrete contain 15% fly ash and 20% slag,its resistance ability to the freeze-thaw impact in seawater is the optimal. Compared to the seawater corrosion,the impact of freeze-thaw cycles to the properties of concrete is severer.

关键词： freeze-thaw damage seawater mass loss relative dynamic elastic modulus

ETV2 expression increases the efficiency of primitive endothelial cell derivation from human embryonic stem cells

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Cell Regeneration 2015年第1期4卷 1-7页

作者： Anne G Lindgren Matthew b Veldman Shuo Lin Department of Molecular Cellular and Developmental biology University of California615 Charles E.Young Drive SouthLos AngelesCA 90095USA

background:Endothelial cells line the luminal surface of blood vessels and form a barrier between the blood and other tissues of the *** variant 2(ETV2)is transiently expressed in both zebrafish and mice and is necessary and sufficient for vascular endothelial cell *** of this gene in early zebrafish and mouse embryos results in ectopic appearance of endothelial *** expression of ETV2 in later development results in only a subset of cells responding to the ***:We have examined the expression pattern of ETV2 in differentiating human embryonic stem cells(ESCs)to determine when the peak of ETV2 expression *** show that overexpression of ETV2 in differentiating human ESC is able to increase the number of endothelial cells generated when administered during or after the endogenous peak of gene ***:Addition of exogenous ETV2 to human ESCs significantly increased the number of cells expressing angioblast genes without arterial or venous *** may be a viable solution to generate in vitro endothelial cells for use in research and in the clinic.

关键词： Human embryonic stem cells Endothelium ETV2 Differentiation

Performance, emission and combustion characteristics of DI diesel engine running on blends of honne oil/diesel fuel/kerosene/DMC

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International Journal of Agricultural and biological Engineering 2011年第3期4卷 48-57页

作者： b.K.Venkanna C.Venkataramana Reddy Department of Mechanical Engineering Basaveshwar Engineering CollegeBagalkot 587102KarnatakaIndia Principal Guru Nanak Institute of TechnologyIbrahimpatnamR.R.District-501506Andra PradeshIndia

Honne oil(tamanu)(H),a non-edible vegetable oil is native for northwards of Northern Marianas islands and the Ryukyu Islands in southern Japan and westward throughout *** has remained as an untapped new possible source of alternative fuel that can be used as diesel engine *** pertaining to use of vegetable oil in diesel engine with kerosene and dimethyl carbonate(DMC)is *** present research is aimed to investigate experimentally the performance,exhaust emission and combustion characteristics of a direct injection(DI)diesel engine,typically used in agricultural sector,over the entire load range,when fuelled with neat diesel(ND)and blends of diesel fuel(D)/DMC/H/kerosene(K).DMC/D/H/K blends have a potential to improve the performance and emissions and to be an alternative to *** have been conducted when fuelled with H20(20%H+80%D),HK(20%H+40%K+40%D)and HKD5(20%H+40%K+35D+5%DMC)to HKD15 in steps of 5%DMC keeping H and K percentages *** emissions(CO,HC and smoke density(SD))of fuel blend HKD15 are found to be lowest,with SD dropping *** NOx level is slightly higher with HKD5 to HKD15 as compared to *** brake thermal efficiency of HKD5 to HKD15 is same and it is higher than that of *** is a good trade off between NOx and *** cylinder pressure and premixed combustion phase increases as DMC content increase.

关键词： diesel engine performance emissions combustion vegetable oil kerosene diesel fuel dimethyl carbonates

Multicast-enabled high-speed VCSEL technology for flexible data center networks

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Optoelectronics Letters 2018年第6期14卷 438-441页

作者： G.M.Isoe S.Wassin T.b.Gibbon Center for broadband Communication Nelson Mandela University

We experimentally demonstrate the multiple signal modulation on a single class 10 G vertical cavity surface emitting laser(VCSEL) carrier at 1 310 nm for next generation multicast-enabled data center networks. A 10 Gbit/s data signal is directly modulated onto a single mode VCSEL carrier. To maximize carrier spectral efficiency, a 2 GHz reference frequency(RF) clock tone is simultaneously modulated on the VCSEL phase attribute. The inherent VCSEL orthogonal polarization bistability with changing bias current is further exploited in transmission of a polarization based pulse per second(PPS) timing clock signal. Therefore, we simultaneously transmit a 10 Gbit/s directly modulated data, 2 GHz phase modulated RF and a polarization-based PPS clock signals using a single mode 10 GHz bandwidth VCSEL carrier. It is the first time that a single class 10 G VCSEL carrier is reported to transmit a directly modulated data, phase modulated RF clock and polarization based PPS timing signal simultaneously in a single wavelength. A of G.652 single mode fibre(SMF) transmission over 3.21 km is experimentally attained. A receiver sensitivity of-15.60 dbm is experimentally obtained for the directly modulated 10 Gbit/s data signal. A 3.21-km-long SMF transmission introduces a penalty of 0.23 db to the data signal. The contribution of a 2 GHz phase modulated RF and a polarization-based PPS clock signal to this penalty is found to be 0.03 db. An RF single-side band(SSb) phase noise values of -82.36 dbc/Hz and -77.97 dbc/Hz are attained without and with simultaneous directly modulated data and polarization-based PPS clock signals respectively for a 3.21-km-long SMF transmission. This work provides an alternative efficient and cost effective technique for simultaneous high-speed multiple information transmission to different network nodes within a data center network through shared network infrastructure.

关键词： VCSEL Multicast-enabled data center networks

Macromolecules Mimicking backbones of Nucleic and Teichoic ***,Some Properties and Applications

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复旦学报（自然科学版） 2007年第5期46卷 557-558页

作者： Stanislaw Penczek Julia b.Pretula Krzysztof Kaluzynski Centre of Molecular and Macromolecular Studies Polish Academy of Sciences 90-363 Lodz Poland

1 Results Several methods have been elaborated in this laboratory allowing preparation of macromolecules with phosphodiester bonds,and having sequence of atoms similar as in the chains of biomacromolecules - nucleic or teichoic acids (TA),namely:-(C)n-O-PO-,where n=2 (for teichoic acids) or *** methods,to be discussed in the lecture,are based on the ring-opening polymerization,transesterification,and recently elaborated direct addition of phosphoric acid to *** the first time an attempt h...

关键词： macromolecules teichoic acid mimicking backbones