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Journal of Palaeogeography 2019年第4期8卷 408-421页

作者： g.Shanmugam Department of Earth and Environmental Sciences The University of Texas at Arlington

In this reply,I respond to 18 issues associated with comments made by Zavala(e.g.,inverse-to normally-graded sequence,origin of massive sands,experimental sandy debris flows,tidal rhythmites,facies models,etc.),and 10 issues associated with comments made by Van Loon et al.(e.g.,16 types of hyperpycnal flows,anthropogenic hyperpycnal flow,etc.).

关键词： Hyperpycnal flows Hyperpycnites Sandy debris flows Turbidity currents

Exact solutions of nonlinear fractional differential equations by (g'/g)-expansion method

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Chinese Physics B 2013年第11期22卷 140-145页

作者： Ahmet Bekir zkan güner Eskisehir Osmangazi University Art-Science Faculty Department of Mathematics-Computer Dumlup nar University School of Applied Sciences Department of Management Information Systems

In this paper, we use the fractional complex transform and the （g＇/g）-expansion method to study the nonlinear fractional differential equations and find the exact solutions. The fractional complex transform is proposed to convert a partial fractional differential equation with Jumarie＇s modified Riemann-Liouville derivative into its ordinary differential equation. It is shown that the considered transform and method are very efficient and powerful in solving wide classes of nonlinear fractional order equations.

关键词： (g'/g)-expansion method time-fractional Burgers equation fractional-order biological popula-tion model space-time fractional Whitham-Broer-Kaup equations

Immobilization of Penicillin g Acylase on Calcined Layered Double Hydroxides

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Chemical Research in Chinese Universities 2003年第3期19卷 324-329页

作者： Evans D.g. Key Laboratory of Science & Technology of Controllable Chemical Reactions

A hydrotalcite-like Mg 2+ /Al 3+ layered double hydroxide(LDH) material was prepared by means of a modified coprecipitation method involving a rapid mixing step followed by a separate aging process. LDH calcined at 500 ℃, denoted as CLDH, was characterized by XRD, IR and BET surface area measurements. CLDH has a poor crystalline MgO-like structure with a high surface area and porosity. CLDH was used as a support for the immobilization of penicillin g acylase(PgA). The effect of varying the immobilization conditions, such as pH, contact time and the ratio of enzyme to support, on the activity of the immobilized enzyme in the hydrolysis of penicillin g has been studied. It was found that the activity of the immobilized enzyme decreased slightly with decreasing pH and reached a maximum after a contact time of 24 h. The activity of the immobilized enzyme increased with increasing the ratio of enzyme to support. It was found that the adsorption of PgA inhibited the expected reaction of CLDH with an aqueous medium to regenerate a LDH phase. Its original activity(36%) after 15 cycles of reuse of the immobilized enzyme was retained, but no further loss in the activity was observed.

关键词： Immobilized enzyme Penicillin g acylase Layered double hydroxide Calcination

Total Syntheses of Favolasins A,E,g and K,Polyketides Isolated from Cultures of the Basidiomycetes Fungi Favolaschia *** 18686 and Favolaschia calocera BCC 36684

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Chinese Journal of Chemistry 2023年第12期41卷 1450-1464页

作者： Bingbing Sheng Ping Lan Jolynn Kiong Zeinab g. Khalil Robert J. Capon Martin g.Banwell Institute for Advanced and Applied Chemical Synthesis College of Pharmacy Jinan University Guangzhou Guangdong 510632 China guangdong Province Key Laboratory of Pharmacodynamic Constituents of TCM & New Drugs Research Jinan University Guangzhou Guangdong 510632 China Institute for Molecular Bioscience The University of Queensland St Lucia QLD 4072 Australia guangdong Key Laboratory for Research and the Development of Natural Drugs The Marine Biomedical Research Institute Guangdong Medical University Zhanjiang Guangdong 524023 China

The structures assigned to all four members,1-4,of the recently reported favolasin class of natural product have been prepared for the first time by chemical ***-Miyaura cross-coupling chemistry was used to establish the associated biaryl *** key step used in preparing the 1,5-benzodioxepin ring system associated with compounds 3 and 4 was the acid-catalyzed 7-exo-tet cyclization of an appropriately substituted 2-(oxiran-2-ylmethoxy)phenol while a base-promoted 6-exo-tet cyclization of the same substrate was used to construct the 2,3-dihydrobenzo[b][1,4]dioxine core of target *** spectral data derived from the four synthetically-produced favolasins matched those reported for the corresponding natural *** biological screening of compounds 1-3 as well as a suite of fourteen precursors reveal that they display no notable anti-bacterial,anti-fungal or anti-tumor activities but congener K(4)is active,in the mM range,against Plasmodium falciparum.

关键词： Total syntheses Favolasins Suzuki-Miyaura cross-coupling Acetalization Anti-malarial

Effect of machining parameters on edge-chipping during drilling of glass using grinding-aided electrochemical discharge machining （g-ECDM）

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Advances in Manufacturing 2018年第2期6卷 215-224页

作者： V. g. Ladeesh R. Manu Department of Mechanical Engineering National Institute of Technology Calicut Calicut Kerala 673601 India

The problem of eliminating edge-chipping at the entrance and exit of the hole while drilling brittle materials is still a challenging task in different industries. grinding- aided electrochemical discharge machining （g-ECDM） is a promising technology for drilling advanced hard-to-ma- chine ceramics, glass, composites, and other brittle mate- rials. Edge-chipping at the entrance of the hole can be fully eliminated by optimizing the machining parameters of g-ECDM. However, edge-chipping at the exit of the hole is difficult to eliminate during the drilling of ceramics and glass. This investigation suggests some practical ways to reduce edge-chipping at the exit of the hole. For this pur- pose, a three-dimensional finite element model was developed, and a coupled field analysis was conducted to study the effect of four parameters, i.e., cutting depth, support length, applied voltage, and pulse-on time, on the maximum normal stress in the region where the edge- chipping initiates. The model is capable of predicting the edge-chipping thickness, and the results predicted by the model are in close agreement with the experiment results. This investigation recommends the use of a low voltage and low pulse-on time at the hole entrance and exit when applying g-ECDM to reduce the edge-chipping thickness. Moreover, the use of a full rigid support in the form of a base plate or sacrificial plate beneath the workpiece can postpone the initiation of chipping by providing support when the tool reaches the bottom layer of the workpiece, thereby reducing the edge-chipping thickness.

关键词： grinding-aided electrochemical dischargemachining (g-ECDM) Finite element analysis Edge-chipping - Maximum normal stress

Microwave assisted synthesis of poly（2-hydroxyethylmethacrylate） grafted agar （Ag-g-P（HEMA）） and its application as a flocculant for wastewater treatment

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Frontiers of Chemical Science and Engineering 2013年第3期7卷 312-321页

作者： gautam SEN g. Usha RANI Sumit MISHRA Department of Applied Chemistry Birla Institute of Technology Mesra Ranchi 835 215 India

Poly（2-hydroxyethylmethacrylate） chains were grafted onto the backbone of agar using a microwave assisted method involving a combination of microwave irradiation and ceric ammonium nitrate to initiate the grafting reaction. The synthesized graft copolymers were characterized by intrinsic viscosity measurements, Fourier transform infrared spectroscopy, elemental analysis （C, H, N, O and S） and scanning electron microscopy. Ag-g-P （HEMA）-2 showed a much higher flocculation efficacy than agar. The optimized dosage of flocculation for Ag-g-P （HEMA）-2 in the wastewater was found to be 0.75 ppm. Compared to agar, Ag-g-P（HEMA）-2 was found to considerably reduce the pollutant load in the wastewater.

关键词： agar flocculant microwave assisted synth- esis jar test protocol poly(HEMA) grafted agar wastewater treatment

Unusual Polarization Properties of Supernova Remnant g4.8＋6.2 at 1400MHz

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Chinese Physics Letters 2003年第6期20卷 969-971页

作者： ZHANgXi-Zhen R.g.Strom W.Reich NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 AstronomicalInstitute UniversityofAmsterdamNetherlands Max-Planck-InstitutfuerRadioastronomie Postfach202453010BonnGermany

Unusual polarization properties of the high galactic latitude supernova remnant (SNR) g4.8+6.2 are reported. The percentage polarization is larger than 70% over the two main shells of g4.8+6.2 at 1400MHz. It is the second SNR with such high polarization at such a low frequency among the known 225SNRs. We show that this is very unusual for an SNR. Its morphology and polarization are very similar to those of the supernova remnant DA530 (g93.0+6.5), which is another high galactic latitude SNR.

关键词： Polarization

Wormhole solutions and energy conditions in f(R,g)gravity

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Communications in Theoretical Physics 2021年第11期73卷 131-141页

作者： M Farasat Shamir g Mustafa Saad Waseem Mushtaq Ahmad National University of Computer and Emerging Sciences Lahore CampusPakistan Department of Mathematics Shanghai UniversityShanghai200444China National University of Computer and Emerging Sciences Chiniot-Faisalabad CampusPakistan

In this manuscript,the traversable wormhole solutions have been explored in modified f(R,g)gravity by taking into consideration the model f(R,g)=R+rg2,where R is the Ricci curvature scalar and g is the gauss–Bonnet *** acceptable form of the redshift function has been incorporated which is a non-constant in nature along with the implementation of those already defined in literature,the two shape functions namely b(r)=r/exp(r-r0)and b(r)=r0log(r+1)/log(r0+1).It is shown by studying the energy condition and through the graphical analysis that the null energy bounds for the effective energy-momentum tensor are generally violated for the presence of the ordinary matter in modified f(R,g)*** conditions associated with the matter content threading the wormhole geometries are evaluated and in general are found to favor the null energy conditions in the vicinity of the wormhole throat,the existence of the nonexotic wormhole geometries threaded by the matter has been confirmed under this gravity.

关键词： f(R,g)gravity energy conditions wormholes shape function

Malaria prevalence in north-eastern Nigeria:A cross-sectional study Houben CH^(1*),Fleischmann H^2,gǜckel M^3

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Asian Pacific Journal of Tropical Medicine 2013年第11期6卷 865-868页

作者： Houben CH Fleischmann H gckel M Diagnostic Center MMM group & Specialist Hospital Yola Hospital RoadP.M.B.2266YolaAdamawa.StateNigeria Medical Mission Institute Tropical MedicineHermann Schell Str 797074 WrzburgGermany Helios Kliniken Schwerin Wismarsche Str 393-39719049 SchwerinGermany

Objective:To assess the prevalence of malaria parasitemia in north-east Nigeria and to evaluate the measures for the prevention of ***:A village in north-eastern Nigeria was selected for the cross sectional study at the height of the rainy season in October 2011.A total of 550 inhabitants of a hamlet were recruited for this *** obtaining the consent individuals received a structured interview and were tested for malaria parasites in their blood *** testing positive for malaria were given a course of artemesinin-based combination therapy（ACT）.Results:A total of 497 inhabitants representing approximately 90 percent of the population participated:a quarter of the study group carried malaria parasitesexclusively Plasmodium falciparum（***）-representing a *** parasite rate（PfPR） of 24.5%.Besides,53/138 in the age group of 2 to g a PfPR2-10 value of 38.4%.Malaria control measures were used in just under a third（157/497） of this *** these measures 28/157（17.8%） still tested positive for ***:The malaria burden is overestimated for this region in north-east *** findings support an intermediate pattern of malaria *** 30%bed nets coverage for malaria control is well below the WHO estimates for 2011.

关键词： Malaria control Malaria endemicity Malaria prevalence Malaria transmission

A Spectral Atlas of F and g Stars

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Chinese Journal of Astronomy and Astrophysics 2004年第3期4卷 279-283页

作者： V.g.Klochkova gangZhao V.E.Panchuk S.V.Ermakov NationalAstronomicalObservatories ChineseAcademyofSciencesBeijing100012 SpecialAstrophysicalObservatoryRussianAcademyofSciences NizhnijArkhyzKarachai-Cherkessia369167Russia

We present an atlas of a group of bright stars in the range of spectral classes F–g and luminosity classes I–V. The spectra were obtained with spectral resolution R ~ 15 000 within spectral region 4500–6620?. Typical spectra of stars with different metallicity [Fe/H] are included. We also show the digital version of the spectral data in FITS format.

关键词： stars: atlas stars: spectral class stars: F-g type