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Facies development and sedimentology of the Middle Miocene carbonates of the Raghama Formation, northeastern saudi Arabia

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Acta Geochimica 2024年第1期43卷 87-96页

作者： Mansour h.Al-hashim Abdelbaset s.El-sorogy Meshal Wadani Department of Geology and Geophysics College of ScienceKing Saud University2455Riyadh 11451Saudi Arabia

Ragahama Formation comprises a siliciclastic continental deposits followed by marine carbonates, representing prograding alluvial fans from adjacent high hinterlands seaward into lagoons and fringing reef environments. The present work aimed to document the facies development and sedimentology of the Raghama carbonates exposed along the eastern coastal plain of the Red sea, northwestern saudi Arabia. Four stratigraphic sections were measured and sampled(D1–D4) and thin sections and major and trace element analyses were prepared and applied for petrographic and geochemical approaches. The carbonates were subdivided into three successive fore-reef, reef-core, and back-reef depositional facies. sandy stromatolitic boundstone, microbial laminites, dolomitic ooidal grainstone, bioclastic coralline algal wackestone, sandy bioclastic wackestone, and coral boundstones were the reported microfacies types. Petrographic analysis reveals that the studied carbonates were affected by dissolution, dolomitization, and aggrading recrystallization, which affects both the original micrite matrix and grains or acts as fracture and veinlet filling leading to widespread vuggy and moldic porosity. No evidence of physical compaction, suggesting rapid lithification and recrystallization during early diagenesis and prior to substantial burial and intensive flushing by meteoric waters. Most of the original microstructure of corals were leached and destructed. This is indicated by the higher depletion in sr and Ca levels and increase in Mg,na, Fe, and Mn levels, especially in section D1, in comparison with the worldwide carbonates.

关键词： Raghama Formation Miocene Diagenesis Geochemistry saudi Arabia

Cr-induced fusion reactions to synthesize superheavy elements

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Nuclear science and Techniques 2024年第5期35卷 122-130页

作者： s.Madhu h.C.Manjunatha N.sowmya B.M.Rajesh L.seenappa R.s.susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)Cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)Cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)Cr+^(243)Am,23.2 fb at 236 MeV for ^(54)Cr+^(247)Cm,95.6 fb at 240 MeV for ^(53)Cr+248Bk,and 1.33 fb at 242 MeV for ^(53)Cr+***,these projected cross sections with excitation energy and beam energy will be useful in future Cr-induced fusion reaction investigations.

关键词： Fusion cross sections Compound nucleus formation probability survival probability Evaporation residue cross sections

Therapeutic nucleic acids in regenerative medicine and tissue repair

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nano Research 2024年第10期17卷 8942-8976页

作者： Qimanguli saiding Duotian Qin soohwan An Dylan Neal Patel Muhammad Muzamil Khan na Kong Wei Tao Center for nanomedicine and Department of Anesthesiology Brigham and Women’s HospitalHarvard Medical SchoolBostonMassachusetts 02115USA

In the vanguard of biomedical innovation,regenerative medicine emerges as a transformative paradigm,concentrating its efforts on rectifying tissue deficits and functional aberrations in patients through the strategic augmentation of endogenous cellular *** to this approach is nucleic acid therapy,which offers a novel pathway for tissue regeneration by modulating key signaling *** one of the most effective ways to regulate cell function,nucleic acids are crucial for various tissue regeneration;however,their in vivo therapeutic applications face substantial challenges,including nuclease degradation,cell membrane impermeability,and targeted intracellular ***-based gene delivery systems offer a solution for stable and localized drug delivery by enabling the controlled overexpression of therapeutic nucleic acids,producing functional regulatory *** review presents examples of nucleic acid applications in regenerative medicine,highlighting the synergy between nucleic acids and biomaterial *** underlines the importance of nucleic acid delivery techniques,the choice of therapeutic nucleic acids,and biomaterials for advancing tissue *** latest developments in designing nucleic acid biomaterial-based delivery vehicles are explored,the mechanism of nucleic acids in tissue regeneration is elucidated,and their limitations are discussed while considering future directions for the clinical translation of nucleic acid-based therapeutics.

关键词： tissue repair nucleic acids biomaterials delivery systems regenerative medicine

Time-dependent model for two-phase flow in ultra-high water-cut reservoirs: Time-varying permeability and relative permeability

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Petroleum science 2024年第4期21卷 2536-2553页

作者： shao-Chun Wang na Zhang Zhi-hao Tang Xue-Fei Zou Qian sun Wei Liu College of Energy Resources Chengdu University of Technology College of Petroleum Engineering Shandong Institute of Petroleum and Chemical Technology

For the ultra-high water-cut reservoirs, after long-term water injection exploitation, the physical properties of the reservoir change and the heterogeneity of the reservoir becomes increasingly severe, which further aggravates the spatial difference of the flow field. In this study, the displacement experiments were employed to investigate the variations in core permeability, porosity, and relative permeability after a large amount of water injection. A relative permeability endpoint model was proposed by utilizing the alternating conditional expectation(ACE) transformation to describe the variation in relative permeability based on the experimental data. Based on the time dependent models for permeability and relative permeability, the traditional oil-water two-phase model was improved and discretized using the mimetic finite difference method(MFD). The two cases were launched to confirm the validation of the proposed model. The impact of time-varying physical features on reservoir production performance was studied in a real water flooding reservoir. The experimental results indicate that the overall relative permeability curve shifts to the right as water injection increases. This shift corresponds to a transition towards a more hydrophilic wettability and a decrease in residual oil saturation. The endpoint model demonstrates excellent accuracy and can be applied to time-varying simulations of reservoir physics. The impact of variations in permeability and relative permeability on the reservoir production performance yields two distinct outcomes. The time-varying permeability of the reservoir results in intensified water channeling and poor development effects. On the other hand, the time-varying relative permeability enhances the oil phase seepage capacity, facilitating oil displacement. The comprehensive time-varying behavior is the result of the combined influence of these two parameters, which closely resemble the actual conditions observed in oil field expl

关键词： Mimetic finite difference Water flooding reservoir Time-varying physical properties Numerical simulation

Transepithelial photorefractive keratectomy without mitomycin-C for irregular astigmatism after femtosecond laser-assisted in situ keratomileusisflap complications

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International Journal of Ophthalmology(English edition) 2024年第6期17卷 1168-1170页

作者： Ning-na Zhang Li-Ming Tao Jing Wang Department of Ophthalmology The Second Affiliated Hospital of Anhui Medical UniversityHefei 230000Anhui ProvinceChina

Dear Editor,W e write to present a case report of transepithelial photorefractive keratectomy(TPRK)without mitomycin-C(MMC)for irregular astigmatism after femtosecond laser-assisted in situ keratomileusis(Fs-LAsIK)flap *** informed consent was obtained from the patient to allow the publication of this case and associated accompanying *** study was conducted in accordance with the helsinki *** is a surgical procedure which uses an excimer laser to ablation of both the corneal epithelium and stroma,which is widely used in clinic[1-2].The procedure may be conducted in cases where there is notable topographic irregularity or scarring following complications with the LAsIK *** haze is a potential complication following TPRK,and the use of MMC as a prophylactic agent against postoperative corneal haze has been demonstrated to significantly reduce its formation after TPRK/photorefractive keratectomy(PRK).

关键词： complications mitomycin epithelium

Alleviation of the plastic deformation of gel ink under strong stress through an esterification of xanthan gum reinforcing its double helix structure

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Chinese Journal of Chemical Engineering 2024年第3期67卷 49-57页

作者： Xiaokun Li Mingyi Wang Zilu Liu song Yang na Xu Wei Zhao Gan Luo shoujun Liu College of Chemical Engineering and Technology Taiyuan University of TechnologyTaiyuan 030024China shanxi Engineering Center of Civil Clean Fuel Taiyuan University of TechnologyTaiyuan 030024China shanxi Coking Coal in Yuncheng salt Refco Group Ltd. Yuncheng 044000China

As a natural organic polymer,xanthan gum(XG)can alleviate the plastic deformation of gel ink under strong stress and realize the reasonable regulation of the rheological properties of gel ***,as the double-helix structure connected by hydrogen bonds cannot resist the mechanical environment of strong stress,XG shows poor shear *** this study,a polymer gel with interpenetrating polymer network structure was prepared by esterifying XG,taking polystyrene maleic anhydride(sMA)as the *** addition to retaining the excellent rheological properties of XG,the generated polymer gel also exhibited high shear *** optimal addition amount of the esterification reaction modifier was determined as mXG:msMA=5:3 according to the gel ink *** this amount,the viscosity of the modified xanthan gum(sXG)gel increased to 1578.8 mPa·s and 100.7 mPa·s at shear rates of 4 s1 and 383 s1,respectively,and the shear resistance increased more than 2 times compared to the unmodified *** is because of the ester bond formed by esterification that the reaction strengthens the interaction between molecular segments,enabling the new gel to resist to strong mechanical *** new polymer gel studied in this paper and the proposed mechanism of action provide new insights for the development of high-end gel ink and also provide theoretical support for the study of rheological properties of non-Newtonian fluids.

关键词： Gel ink Xanthan gum Esterification simulation shear resistance Gels

Responses of plant diversity and soil microorganism diversity to nitrogen addition in the desert steppe,China

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Journal of Arid Land 2024年第3期16卷 447-459页

作者： YE he hONG Mei XU Xuehui LIANG Zhiwei JIANG na TU nare WU Zhendan College of Grassland Resources and EnvironmentInner Mongolia Agricultural UniversityInner Mongolia Key Laboratory of Soil Quality and Nutrient ResourcesHohhot 010018China Key Laboratory of Agricultural Ecological security and Green Development at University of Inner Mongolia Hohhot 010018China

Nitrogen(N)deposition is a significant aspect of global change and poses a threat to terrestrial *** impact of plant-soil microbe relationships to N deposition has recently attracted considerable *** microorganisms have been proven to provide nutrients for specific plant growth,especially in nutrient-poor desert steppe ***,the effects of N deposition on plant-soil microbial community interactions in such ecosystems remain poorly *** investigate these effects,we conducted a 6-year N-addition field experiment in a stipa breviflora *** steppe in Inner Mongolia Autonomous Region,*** N treatment levels(N0,N30,N50,and N100,corresponding to 0,30,50,and 100 kg N/(hm2•a),respectively)were applied to simulate atmospheric N *** results showed that N deposition did not significantly affect the aboveground biomass of desert steppe plants.N deposition did not significantly reduce the alfa-diversity of plant and microbial communities in the desert steppe,and low and mediate N additions(N30 and N50)had a promoting effect on *** variation pattern of plant shannon index was consistent with that of the soil bacterial Chao1 index.N deposition significantly affected the beta-diversity of plants and soil bacteria,but did not significantly affect fungal *** conclusion,N deposition led to co-evolution between desert steppe plants and soil bacterial communities,while fungal communities exhibited strong stability and did not undergo significant *** findings help clarify atmospheric N deposition effects on the ecological health and function of the desert steppe.

关键词： soil microorganisms plant-microbial community interaction plant diversity nitrogen deposition desert steppe

Nodal solutions with a Prescribed Number of Nodes for Quasilinear schr?dinger Equations with a Cubic Term

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Journal of Mathematical Research with Applications 2024年第5期44卷 681-696页

作者： Jing LAI na LIU Tao WANG College of Mathematics and Computing science Hunan University of Science and Technology

This paper is concerned with the existence of nodal solutions for the following quasilinear schr?dinger equation with a cubic term ■ where N ≥ 3, λ > 0, the function V（|x|） is a radially symmetric and positive potential. By using the variational method and energy comparison method, for any given integer k ≥ 1, the above equation admits a radial nodal solution Uk,4λhaving exactly k nodes via a limit ***, the energy of Uk,4λis monotonically increasing in k and for any sequence {λ_n}, up to a subsequence,■ converges strongly to some ■ as λ_n→+∞, which is a radial nodal solution with exactly k nodes of the classical schr¨dinger equation ■ Our results extend the existing ones in the literature from the super-cubic case to the cubic case.

关键词： quasilinear schrödinger equations nodal solutions limit approach variational method

Construction of 2D/2D Ti_(3)C_(2)T_(x)MXene/Cds heterojunction with photothermal effect for efficient photocatalytic hydrogen production

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Journal of Materials science & Technology 2024年第4期171卷 1-9页

作者： T.Y.huang Z.Yang s.Y.Yang Z.h.Dai Y.J.Liu J.h.Liao G.Y.Zhong Z.J.Xie Y.P.Fang s.s.Zhang Key Laboratory for Biobased Materials and Energy of Ministry of Education Guangdong Laboratory for Lingnan Modern AgricultureCollege of Materials and EnergySouth China Agricultural UniversityGuangzhou 510643China school of Physics and Optoelectronics South China University of TechnologyGuangzhou 510640China school of Chemical Engineering and Energy Technology Guangdong Provincial Key Laboratory of Distributed Energy SystemsDongguan University of TechnologyDongguan 523808China

The insensitivity of semiconductors to visible and infrared light is a key constraint on the utilization of light energy in photocatalytic *** photocatalysts with full-spectrum absorption through surface engineering is an effective approach to fully harnessing light energy in semiconductor ***,a novel stable Ti_(3)C_(2)T_(x)MXene/Cds heterojunction catalyst is obtained by in-situ epitaxial growth of two-dimensional(2D)Cds nanosheets on 2D MXene interface via a solvothermal *** exceptional light absorption properties of MXene confer outstanding full-spectrum driven photocat-alytic hydrogen evolution capability upon the heterogeneous *** unique 2D/2D structure effectively mitigated the recombination of photogenerated carriers,enhancing the photocatalytic performance of the ***,the composite catalyst exhibits a significantly higher surface temperature of 80.4℃under visible light irradiation at an intensity of 0.1 W/cm^(2),which is 1.84 times higher than that of *** irradiation of visible and near infrared light,the composite catalyst with photothermal ef-fect demonstrates a remarkable hydrogen evolution rate of 65.4 mmol g^(-1)h^(-1),which is 7.2 times higher than that of Cds *** study introduces a novel approach for constructing full-spectrum absorption catalysts and expands the application of the photothermal effect in photocatalytic hydrogen evolution research.

关键词： Two-dimensional structure heterostructure Photothermal effect Photocatalyst hydrogen evolution