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Disentangling the contributing components of stream water by using environmental tracers

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Journal of Mountain Science 2025年第1期22卷 260-277页

作者： Abul amir KHAN Naresh Chandra PANT Amity Centre for Air Pollution Control(ACAPC)&Amity Centre for Ocean Atmospheric Science and Technology(ACOAST) Amity University Haryana(AUH)Gurugram-122413India Department of Geology University of DelhiNorth CampusDelhi-11007India

Identifying the various components contributing to river discharge can be *** study relies on stable isotopes and electrical conductivity(EC)of water as tracers to distinguish the different components contributing to total river ***,we have made an effort to comprehend the processes that may influence glacier ice melt as well as the limits of oxygen-based hydrograph *** distinct geographic domains in terms of climates and topographies were *** first study site represents the upper Ganga catchment(central Himalaya),while the second site is located in the Chandra sub-basin in western *** in estimating the proportion of glacier melt in isotope mixing model are likely if end-member isotopic compositions,are not well defined,particularly for *** separation results indicate that snowmelt is the largest contributor to total river flow in both *** contribution of snowmelt to the total runoff of the upper Ganga ranged from~60%to 70%.The estimated contributions of glacier melt varied from 36%to 63%in upper Ganga headwater to 6%to 15%at Devprayag and~8%at *** the Hamtah River,glacier and snowmelt contributions,quantified using a two-component mixing model,ranged from 10%to 14%during the pre-and postmonsoon seasons of *** significant spatial and temporal variability,coupled with overlapping isotopic signatures,suggests complex glacio-fluvial interactions in these *** slow-moving air masses with whirling motion closer to the study area irrespective of the direction,and air parcels coming through Bay of Bengal branch are characterized by depleted isotopic rainfall compared to air masses originating from the Arabian Sea.

关键词： Snowmelt Glacier melt Oxygen isotopes Bhagirathi River Alaknanda River Hamtah

Bi-directional interaction of joint shear strength in non-seismically designed corner RC beam-column connections under seismic loading

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Earthquake Engineering and Engineering Vibration 2025年第1期24卷 135-153页

作者： Mohammad amir Najafgholipour Negin Ahmadi rad Akanshu Sharma Department of Civil and Environmental Engineering Shiraz University of TechnologyShiraz ***Iran Lyles School of Civil Engineering Purdue UniversityWest LafayetteIN 47907-2050USA

Non-seismically designed(NSD)beam-column joints are susceptible to joint shear failure under seismic *** significant research is available on the seismic behavior of such joints of planar frames,the information on the seismic behavior of joints of space frames(3D joints)is *** 3D joints are subjected to bi-directional excitation,which results in an interaction between the shear strength obtained for the joint in the two orthogonal directions *** bi-directional seismic behavior of corner reinforced concrete(RC)joints is the focus of this ***,a detailed finite element(FE)model using the FE software Abaqus,is developed and validated using the test results from the *** validated modeling procedure is used to conduct a parametric study to investigate the influence of different parameters such as concrete strength,dimensions of main and transverse beams framing into the joint,presence or absence of a slab,axial load ratio and loading direction on the seismic behavior of *** subjecting the models to different combinations of loads on the beams along perpendicular directions,the interaction of the joint shear strength in two orthogonal directions is *** comparison of the interaction curves of the joints obtained from the numerical study with a quadratic(circular)interaction curve indicates that in a majority of cases,the quadratic interaction model can represent the strength interaction diagrams of RC beam to column connections with governing joint shear failure reasonably well.

关键词： beam-column joints joint shear failure bidirectional loading interaction curve finite element study

Sulfur metabolism under stress:Oxidized glutathione inhibits methionine biosynthesis by destabilizing the enzyme cystathionineγ-synthase

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Journal of Integrative Plant Biology 2025年第1期67卷 87-100页

作者： Yael Hacham Alex Kaplan Elad Cohen Maayan Gal Rachel amir Laboratory of Plant Science MigalGalilee Research InstituteKiryat Shmona 11016Israel Tel-Hai College Upper Galilee 11016Israel Department of Oral Biology Goldschleger School of Dental MedicineFaculty of MedicineTel Aviv UniversityTel Aviv 6997801Israel

Cysteine is the precursor for the biosynthesis of glutathione,a key stress-protective metabolite,and methionine,which is imperative for cell growth and protein *** exact mechanism that governs the routing of cysteine toward glutathione or methionine during stresses remains *** study reveals that under oxidative stress,methionine and glutathione compete for cysteine and that the increased oxidized glutathione(GSSG)levels under stress hinder methionine ***,we find that inhibition occurs as GSSG binds to and accelerates the degradation of cystathionineγ-synthase,a key enzyme in the methionine synthesis ***,this leads to a reduction in the flux toward methionine-derived metabolites and redirects cysteine utilization toward glutathione,thereby enhancing plant *** study suggests a novel regulatory feedback loop involving glutathione,methionine,and cysteine,shedding light on the plant stress response and the adaptive rerouting of *** findings offer new insights into the intricate balance of growth and protection in plants and its impact on their nutritional value due to low methionine levels under stress.

关键词： cystathionineγ-synthase(CGS) cysteine glutathione metabolic competition methionine oxidative stress sulfur metabolism tobacco

Evidence for active generation and seepage of sub-salt natural gas/condensate blend in the east offshore Nile Delta, Egypt: Integrated geochemical, petrophysical and seismic attribute approaches

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Petroleum Science 2025年第1期22卷 130-150页

作者： Mahmoud Leila Ahmed A.Radwan amir Ismail Emad A.Eysa Geology Department Faculty of Science Mansoura University School of Mining and Geosciences Nazarbayev University Department of Geology Faculty of Science Al-Azhar UniversityAssiut Branch Department of Geology Faculty of Science Helwan University Department of Physical and Environmental Sciences Texas A&M University—Corpus Christi Geology Department Faculty of Science Zagazig University

Offshore Nile Delta in Egypt represents an enormous hydrocarbon province with recent projected gas and condensate discoveries of more than 50 trillion cubic feet “TCF”. Most of these occur in the post-salt hydrocarbon plays where biogenic gases are dominant. This study integrates organic geochemistry,seismic geomorphology and petrophysics in order to decipher the origin, and accumulation conditions of the wet gas/condensate blend in the Upper Miocene sub-salt Wakar Formation sandstones in Port Fouad Marine “PFM” Field, offshore Nile Delta. Hydrocarbon pay zones are scattered thin（ 1 w.t.%, hydrogen index“HI” > 200 mg HC/g TOC） and mature(Tmax> 430°C, vitrinite reflectance “VR” > 0.6 %R_o), source rocks are restricted to Upper Miocene Wakar and Oligo-Miocene Tineh formations. The latter contains more mature organofacies（up to 1.2 %R_o） and type II/III kerogen, thereby demonstrating a good capability to generate wet gases. The studied gas is wet and has thermogenic origin with signs of secondary microbial alteration, whereas the condensate contains a mixture of marine and terrestrial input. Molecular biomarkers of the condensate, isotopic and molecular composition of the gas reveals a generation of condensate prior to gas expulsion from the source. The Wakar sandstones have a heterogeneous pore system where three reservoir rock types（RRTI, RRTII and RRTIII）. RRTI rocks present the bulk composition of the Wakar pay zones. Spatial distribution of RRTI facies likely control the accumulation of the sub-salt hydrocarbons. Our results provide a new evidence on an active petroleum system in the sub-salt Paleogene successions in the offshore Nile Delta where concomitant generation of ga

关键词： Petrophysical evaluation Source rock Hydrocarbon geochemistry Biomarkers Gas chimneys Rock-typing

A New Antenna Selection Scheme for MIMO–NOMA Systems with Multiple-Antenna Users

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China Communications 2025年第2期22卷 160-172页

作者： Ehsan Alemzadeh amir Masoud Rabiei School of Electrical and Computer Engineering College of EngineeringUniversity of TehranTehranIran

Non-orthogonal multiple access(NOMA)is a promising technology for the next generation wireless communication *** benefits of this technology can be further enhanced through deployment in conjunction with multiple-input multipleoutput(MIMO)*** selection plays a critical role in MIMO–NOMA systems as it has the potential to significantly reduce the cost and complexity associated with radio frequency *** paper considers antenna selection for downlink MIMO–NOMA networks with multiple-antenna basestation(BS)and multiple-antenna user equipments(UEs).An iterative antenna selection scheme is developed for a two-user system,and to determine the initial power required for this selection scheme,a power estimation method is also *** proposed algorithm is then extended to a general multiuser NOMA *** results demonstrate that the proposed antenna selection algorithm achieves near-optimal performance with much lower computational complexity in both two-user and multiuser scenarios.

关键词： antenna selection MIMO NOMA power allocation

CSRWA:Covert and Severe Attacks Resistant Watermarking Algorithm

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Computers, Materials & Continua 2025年第1期82卷 1027-1047页

作者： Balsam Dhyia Majeed amir Hossein Taherinia Hadi Sadoghi Yazdi Ahad Harati Faculty of Engineering Ferdowsi University of MashhadMashhad***Iran Department of Computer Techniques Engineering Imam Al-Kadhum CollegeBaghdad10087Iraq

Watermarking is embedding visible or invisible data within media to verify its authenticity or protect *** watermark is embedded in significant spatial or frequency features of the media to make it more resistant to intentional or unintentional *** of these features are important perceptual features according to the human visual system(HVS),which means that the embedded watermark should be imperceptible in these ***,both the designers of watermarking algorithms and potential attackers must consider these perceptual features when carrying out their *** two roles will be considered in this paper when designing a robust watermarking algorithm against the most harmful attacks,like volumetric scaling,histogram equalization,and non-conventional watermarking attacks like the Denoising Convolution Neural Network(DnCNN),which must be considered in watermarking algorithm design due to its rising role in the state-of-the-art *** DnCNN is initialized and trained using watermarked image samples created by our proposed Covert and Severe Attacks Resistant Watermarking Algorithm(CSRWA)to prove its *** this algorithm to satisfy the robustness and imperceptibility tradeoff,implementing the Dither Modulation(DM)algorithm is boosted by utilizing the Just Noticeable Distortion(JND)principle to get an improved performance in this ***,luminance,inter and intra-block contrast are used to adjust the JND values.

关键词： Covert attack digital watermarking DnCNN JND perceptual model robustness

Geochemistry and mineral chemistry of granitic rocks from west Wadi El Gemal area,southern Eastern Desert of Egypt:Indicators for highly fractionated syn-to post-collisional Neoproterozoic felsic magmatism

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Acta Geochimica 2025年第1期44卷 163-188页

作者： Hesham Mokhtar Adel A.Surour Mokhles K.Azer Minghua Ren amir Said Department of Geology Faculty of ScienceCairo UniversityGiza 12613Egypt Department of Geological Sciences Faculty of ScienceGalala UniversityNew Galala City 43511Egypt Department of Geological Sciences National Research CentreDokkiGiza 12622Egypt Department of Geoscience University of Nevada Las VegasLas VegasNV 89154-4010USA

Leucogranite,pegmatite,and aplite from selected areas in the Wadi El Gemal area in the southern Eastern Desert of Egypt were investigated geochemically for their *** rocks represent a significant episode of felsic magmatism during the late stage of the Pan-African orogeny in the evolution of the Arabian–Nubian Shield(ANS)during the Late *** a petrographic basis,the leucogranite is sometimes garnetiferous and can be distinguished into monzogranite,syenogranite,and alkali feldspar *** analyses of muscovite,biotite,garnet,and apatite reveal the magmatic nature of the studied *** investigated leucogranite,pegmatite,and aplite are alkali-calcic,calc-alkaline,and *** peraluminous nature of these rocks is evidenced by using the chemical analyses of *** studied rocks show a slight enrichment in light rare-earth elements(LREEs)and large-ion lithophile elements(LILE,especially Rb and Th),with an insignificant depletion of heavy rareearth elements(HREEs).On a geochemical basis,the leucogranite,pegmatite,and aplite in the study area crystallized from multiple-sourced melts that include mafic,metagraywake,and *** were derived from melts generated at crystallization temperatures around 568-900℃ for leucogranite,553-781℃ for pegmatite,and 639-779℃ for aplite based on the Zr saturation geothermometers,and at a pressure around 0.39-0.48 GPa,*** depth *** studied felsic rocks have strong negative Eu anomalies,which are very consistent with an upper crust composition,indicating fractionation of feldspar ***,they show a moderate La/Sm ratio indicating combined magmatic processes represented by partial melting and fractional *** of whole-rock chemical composition and mineral microanalysis suggests that felsic magmatism in the west Wadi El Gemal area produced voluminous masses of syn-to post-collisional granite,pegmatite,and *** evolutionary three-

关键词： Leucogranite Pegmatite Aplite Wadi El Gemal Petrogenesis Syn-collisional Post-collisional

An effective stress-based DSC model for predicting hydromechanical shear behavior of unsaturated collapsible soils subjected to initial shear stress

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Journal of Rock Mechanics and Geotechnical Engineering 2025年第1期17卷 539-555页

作者： Saman Soleymani Borujerdi S.Mohsen Haeri amir Akbari Garakani Chandrakant SDesai Civil Engineering Department Sharif University of TechnologyTehranIran Power Industry Structures Research Department Niroo Research InstituteTehranIran Department of Civil and Architectural Engineering and Mechanics University of ArizonaArizonaUSA

Evaluation of hydromechanical shear behavior of unsaturated soils is still a challenging issue. The time and cost needed for conducting precise experimental investigation on shear behavior of unsaturated soils have encouraged several investigators to develop analytical, empirical, or semi-empirical models for predicting the shear behavior of unsaturated soils. However, most of the previously proposed models are for specimens subjected to the isotropic state of stress, without considering the effect of initial shear stress. In this study, a hydromechanical constitutive model is proposed for unsaturated collapsible soils during shearing, with consideration of the effect of the initial shear stress. The model implements an effective stress-based disturbed state concept (DSC) to predict the stress-strain behavior of the soil. Accordingly, material/state variables were defined for both the start of the shearing stage and the critical state of the soil. A series of laboratory tests was performed using a fully automated unsaturated triaxial device to verify the proposed model. The experimental program included 23 suction-controlled unsaturated triaxial shear tests on reconstituted specimens of Gorgan clayey loess wetted to different levels of suctions under both isotropic and anisotropic stress states. The results show excellent agreement between the prediction by the proposed model and the experimental results.

关键词： Unsaturated collapsible soil Initial shear stress Hydromechanical shear behavior Effective stress Disturbed state concept Critical state

Synergistic effect of nitrocellulose coating on structural and reactivity stabilization of ammonium nitrate oxidizer

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Defence Technology(防务技术) 2025年第1期43卷 35-43页

作者： amir Abdelaziz Djalal Trache Ahmed Fouzi Tarchoun Hani Boukeciat Yash Pal Sourbh Thakur Weiqiang Pang Thomas M.Klapötke Energetic Materials Laboratory(EMLab) Teaching and Research Unit of Energetic ProcessesEcole Militaire PolytechniqueBP 17 Bordj El-BahriAlgiers 16046Algeria School of Aeronautical Science Hindustan Institute of Technology and ScienceChennai 603103India Department of Organic Chemistry Bioorganic Chemistry and BiotechnologySilesian University of TechnologyB.Krzywoustego 4Gliwice 44–100Poland Xi'an Modern Chemistry Research Institute 168 Zhangba Rd.EastXi'an 710065China Energetic Materials Research Department of ChemistryLudwig-Maximilian UniversityMunich Butenandtstrasse 5-13(D)Munich D-81377Germany

The present work aims to stabilize the room temperature allotropic transition of ammonium nitrate(AN)particles utilizing a microencapsulation technique,which involves solvent/non-solvent in which nitrocellulose(NC)has been employed as a coating *** SEM micrographs revealed distinct features of both pure AN and NC,contrasting with the irregular granular surface topography of the coated AN particles,demonstrating the adherence of NC on the AN *** analysis via infrared spectroscopy(IR)demonstrated a successful association of AN and NC,with slight shifts observed in IR bands indicating interfacial *** X-ray Diffraction(PXRD)analysis further elucidated the structural changes induced by the coating process,revealing that the NC coating altered the crystallization pattern of its pure *** analysis demonstrates distinct profiles for pure and coated AN,for which the coated sample exhibits a temperature increase and an enthalpy decrease of the room temperature allotropic transition by 6℃,and 36%,***,the presence of NC coating alters the intermolecular forces within the composite system,leading to a reduction in melting enthalpy of coated AN by~39%compared to pure *** thermal decomposition analysis shows a two-step thermolysis process for coated AN,with a significant increase in the released heat by about 78%accompanied by an increase in the activation barrier of NC and AN thermolysis,demonstrating a stabilized reactivity of the AN-NC *** findings highlight the synergistic effect of NC coating on AN particles,which contributed to a structural and reactive stabilization of both AN and NC,proving the potential application of NC-coated AN as a strategically advantageous oxidizer in composite solid propellant formulations.

关键词： Ammonium nitrate Nitrocellulose Stabilization Coating Thermolysis kinetics