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Sediment discharge of the Yellow River, China: past, present and future——A synthesis

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Acta Oceanologica Sinica 2015年第2期34卷 1-8页

作者： ReN Mei'e Key Laboratory of Coast and Island Development of Ministry of education School of Geographic and Oceanographic Sciences Nanjing University

The Yellow River cut through Sanmenxia Gorge and discharged into the sea via the North China Plain in 150 ka BP; since then, around 86 000 × 108 t sediment has been transported passing Sanmenxia Gorge. Based on land use and land cover changes in Loess Plateau and other available evidence, an estimate of the Yellow River sediment budget is presented here： about 72% of the sedimentary material was trapped in the North China Plain and the remainder（i.e., 26%） escaped to the sea. At the present stage, 〈 0.2×108 t/a suspended sediment of the Yellow River enter the northern Yellow Sea. The transport pattern is determined mainly by the shelf current system. Annually 0.2×108–0.3×108 t of suspended particles are carried to the east China Sea; the materials are derived mainly from coastal and subaqueous delta erosion associated with the abandoned Yellow River on the Jiangsu coast. Since 1972, the lower Yellow River started to have a situation of continuous no-flow. During 1996–2000, the annual water flow and sediment discharge are only 19%, as compared with normal years（i.e., average for 1950–1979）. In response to global warming and increase of water diversion from the Yellow River for industrial and urban use, the sediment flux of the Yellow River to the sea will most likely remain small in the next two to three decades.

关键词： Yellow River Loess Plateau sediment budget transport patterns sediment retention

FATIGUe CRACK PROPAGATION OF Ni-BASe SUPeRALLOYS

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Acta Metallurgica Sinica(english Letters) 2005年第1期18卷 55-64页

作者： e.Barbero Dept. of Mechanical & Aerospace engineering West Virginia University Morgantown WV 26506-6106 USA

Time-dependent Fatigue Crack Propagation (FCP) behaviors of five Ni-base superalloys were investigated at various temperatures under fatigue with various holding times and sustained loading conditions. The new concept of damage zone is defined and employed to evaluate the alloys' resistance to hold-time FCP. A special testing procedure is designed to get the maximum damage zone of the alloys. Udimet 720 and Waspaloy show shorter damage zones than alloys 706 and 718. The fractographical analyses show that the fracture surfaces of the specimens under hold-time fatigue conditions are mixtures with intergranular and transgranular modes. As the extension of holding time per cycle, the portion of intergranular fracture increases, The effects of loading stress intensity, temperature, holding time, alloy chemistry, and alloy mi-crostructure on damage zone and the crack growth behaviors are studied. Hold-time usually increases the alloy's FCP rate, but there are few exemptions. For instance, the steady state hold-time FCP rate of Waspaloy at 760℃ is lower than that without hold-time. The beneficial effect of hold-time was attributed to the creep caused stress relaxation during the hold-time.

关键词： Ni-base superalloys fatigue crack growth hold-time

Search for a natural scientific measure of economy

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Frontiers of environmental Science & engineering 2011年第1期5卷 111-118页

作者： John e COULTeR Xiwangzhuang Shuangqing RdHaidianBeijing 100084China

Through human history,wealth has been measured in grain,gold,and,now,*** counterfeiting of coins and notes goes back a long way,it is only with electronic financial accounting in a global economy tainted by toxic loans and imaginary funds that there is an urgency to search for a realistic objective way to monitor and regulate what we are doing to our earth and *** schemes using analysis of utility functions,oil equivalents,entropy,energy,and other units have been tried and,while helping to understand some basic processes and flows,have always been swamped by the machinations of financiers and the attention big sums of money ***,the concept of exergy,pioneered in eastern europe in the 1950s,is being researched,developed,and applied,especially in China,driven by the desperation to measure the reality beyond the twin specters of global financial and environmental crises.A rough inventory of the matter in the biosphere at the coordinate details of an angstrom and an appreciation of how humans harness and manipulate electromagnetic forces can be enlightening as to what is and is not *** that understanding,any financial estimate and proposed stimulus packages or IMF reform will be wildly wrong and may even be headed in the wrong direction.

关键词： climate change financial crisis energy exergy environment

A New Fractional Model for the Falling Body Problem

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Chinese Physics Letters 2017年第2期34卷 1-3页

作者： A.ebaid B.Masaedeh e.e1-Zahar Department of Mathematics Faculty of ScienceTabuk UniversityP.O.Box 741Tabuk 71491Kingdom of Saudi Arabia Department of Mathematics Faculty of Sciences and HumanitiesPrince Sattam Bin Abdulaziz UniversityA1kharj11942Kingdom of Saudi Arabia Department of Basic engineering Science Faculty of EngineeringShebin El-Kom32511Menofia UniversityEgypt

Recently, a conformable fractional derivative has been proposed to calculate the derivative of non-integer order of time functions. It has been shown that this new fractional derivative definition obeys many advantages over the preceding definitions. For mathematical models in applied sciences and to preserve the dimensionality of the physical quantities, an auxiliary parameter （~r） which has the dimension of seconds should be implemented in the fractional derivative definition. We obtain analytic solutions for the resulting conformable fractional differential equations describing the vertical velocity and the height of the falling body. It is shown that the dimensions of velocity and height are always correct without any restrictions on the auxiliary parameter cr which contradicts with the results in the literature when applying the Caputo definition to the same problem. This may open the door for many future works either to describe the role of such an auxiliary parameter or to derive a more suitable definition for the fractional derivative.

关键词： A New Fractional Model for the Falling Body Problem

Advances and challenges in diagnosing and managing adult autoimmune enteropathy

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World Journal of Gastroenterology 2025年第2期31卷 128-131页

作者： Grigorios Christodoulidis Sara e Agko Marina N Kouliou Konstantinos e Koumarelas Dimitris Zacharoulis Department of General Surgery University Hospital of LarissaLarissa 41110Greece Department of Intensive Care Unit Asklepios Paulinen Clinic WiesbadenWiesbaden 65197Germany Department of emergency Medicine General Hospital of LarissaLarissa 41221Greece Department of Surgery University Hospital of LarissaLarissa 41334Greece

Autoimmune enteropathy(AIe)is a rare immune mediated disorder primarily affecting children,characterized by chronic diarrhea,malabsorption,vomiting,weight loss and villous *** has also been observed in adults presenting diagnostic and treatment challenges due to its overlap with other gastrointestinal disorders such as celiac *** diagnostic criteria for AIe include small bowel villous atrophy,lack of response to dietary restrictions,presence of anti-enterocyte antibodies,and predisposition to autoimmunity without severe *** criteria emphasize characteristic histological findings and exclusion of other causes of villous *** is associated with various autoimmune disorders and can present with overlapping features with Celiac disease,including villous atrophy but without significant intraepithelial *** primarily involves immunosuppression using corticosteroids,calcineurin inhibitors,and anti-tumor necrosis factor therapy,alongside nutri-tional *** the challenges,understanding AIe’s diverse manifest-ations and improving diagnostic criteria are essential for effective management and improved patient *** research is needed to elucidate the pathogenesis,disease progression and long-term outcomes of AIe.

关键词： Autoimmune enteropathy Diagnosis Prognosis Adult autoimmune enter-opathy and challenges Autoimmune enteropathy and treatment Autoimmune enteropathy and diagnostic criteria Pathophysiology of autoimmune enteropathy

Possibility of observation of hidden-bottom pentaquark resonances in bottomonium photoproduction on protons and nuclei near threshold

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Chinese Physics C 2020年第10期44卷 87-97页

作者： e.Ya.Paryev Institute for Nuclear Research Russian Academy of SciencesMoscow 117312Russia Institute for Theoretical and experimental Physics Moscow 117218Russia

We study theΥ(1S)meson photoproduction on protons and nuclei at near-threshold center-of-mass energies below 11.4 GeV(or at the corresponding photon laboratory energies eγbelow 68.8 GeV).We calculate the absolute excitation functions for the nonresonant and resonant photoproduction ofΥ(1S)mesons off protons at incident photon laboratory energies of 63-68 GeV by considering direct(γp→Υ(1S)p)and two-step(γp→P^+b(11080)→Υ(1S)p,γp→P^+b(11125)→Υ(1S)p,γp→P^+b(11130)→Υ(1S)p)Υ(1S)production channels within different scenarios for the nonresonant total cross section of the elementary reactionγp→Υ(1S)p and for branching ratios of the decays P^+b(11080)→Υ(1S)p,P^+b(11125)→Υ(1S)p,and P^+b(11130)→Υ(1S)*** also calculate an analogous function for the photoproduction ofΥ(1S)mesons on the 12C and 208Pb target nuclei in the near-threshold center-of-mass beam energy region of 9.0-11.4 GeV by considering the respective incoherent direct(γN→Υ(1S)N)and two-step(γp→P^+b(11080)→Υ(1S)p,γp→P^+b(11125)→Υ(1S)p,γp→P^+b(11130)→Υ(1S)p andγn→P^0b(11080)→Υ(1S)n,γn→P^0b(11125)→Υ(1S)n,γn→P^0b(11130)→Υ(1S)n)Υ(1S))production processes using a nuclear spectral function *** demonstrate that a detailed scan of theΥ(1S)total photoproduction cross section on proton and nuclear targets in the near-threshold energy region in future high-precision experiments at the proposed high-luminosity electron-ion colliders eIC and eicC in the US and China should provide a definite result for or against the existence of the nonstrange hidden-bottom pentaquark statesP^+bi and P^0bi(i=1,2,3)as well as clarify their decay rates.

关键词： photon-nucleus reactions bottomonium production hidden-bottom pentaquarks

Near-threshold K^*(892)^+ meson production in the interaction of π−mesons with nuclei

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Chinese Physics C 2020年第11期44卷 168-178页

作者： e.Ya.Paryev Institute for Nuclear Research Russian Academy of SciencesMoscow 117312Russia Institute for Theoretical and experimental Physics Moscow 117218Russia

We study the inclusive production of strange vector K^∗(892)^+ mesons in π−A reactions at near-threshold laboratory incident pion momenta of 1.4-2.0 GeV/c via a nuclear spectral function *** approach accounts for incoherent primary π−meson-proton π−p→K^∗(892)^+Σ^− production processes as well as the influence of the scalar K^∗(892)^+-nucleus potential(or the K^∗(892)^+ in-medium mass shift)on these *** calculate the absolute differential and total cross sections for the production of K∗(892)+mesons from carbon and tungsten nuclei at laboratory angles of 0∘-45∘and at the aforementioned momenta in five scenarios for the aforenoted *** show that the K^∗(892)^+ momentum distributions and their excitation functions(absolute and relative)possess a high sensitivity to changes in the in-medium K^∗(892)^+ mass shift in the low-momentum region of 0.1-0.6 GeV/***,the measurement of such observables in a dedicated experiment at the GSI pion beam facility in the near-threshold momentum domain will allow us to get valuable information on the K^∗(892)^+ in-medium properties.

关键词： pion-nucleus reactions strange vector meson production in-medium effects

Investigating the impact of the universal function of the nuclear proximity potential in heavy-ion fusion cross sections

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Communications in Theoretical Physics 2024年第5期76卷 86-93页

作者： R Gharaei e Sarvari Department of Physics Sciences FacultyHakim Sabzevari UniversityPO Box 397SabzevarIran Department of Physics Faculty of ScienceFerdowsi University of MashhadPO Box 91775-1436MashhadIran Science Faculty Department of PhysicsTarbiat Modares UniversityTehranIran

The fusion barriers and cross sections of 15 colliding systems with 320≤Z_(1)Z_(2)≤1512 are investigated in detail to understand the influence of the universal function of proximity potential formalism in the heavy-ion fusion *** realize this goal,we select three versions of the phenomenological proximity potentials,including Prox.77,Zhang 2013,and Guo 2013,to calculate the nucleus-nucleus *** experimental fusion cross sections for the selected reactions are analyzed using the standard coupled-channel calculations,including couplings to the low-lying 2^(+)and 3^(-)states in the target and *** calculated results show that the universal functions of the Guo 2013 and Prox.77 models provide the lowest and highest fusion barriers,*** addition,it is found that the height of the fusion barriers is enhanced by increasing the mass number of the projectile from light to heavy *** highest sensitivity to the mass number of the projectile belongs to the results of Prox.77.A discussion is also presented on the influence of the universal function on the radial behavior of the interaction potential in the allowed region for overlapping *** results reveal that the best fit to the experimental data of the fusion cross sections for the reactions involving light and medium nuclei is obtained using the universal function of the Zhang 2013 *** the heavier systems,the results of the Guo 2013 model at sub-barrier energies provide a good description of the available data.

关键词： fusion reactions proximity-type potentials universal function coupled-channel calculations

CLASSIFICATIONS OF DUPIN HYPeRSURFACeS IN LIe SPHeRe GeOMeTRY

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Acta Mathematica Scientia 2024年第1期44卷 1-36页

作者： Thomas e.CeCIL Department of Mathematics and Computer Science College of the Holy CrossWorcesterMA01610USA

This is a survey of local and global classification results concerning Dupin hypersurfaces in S^(n)(or R^(n))that have been obtained in the context of Lie sphere *** emphasis is on results that relate Dupin hypersurfaces to isoparametric hypersurfaces in *** with these classification results,many important concepts from Lie sphere geometry,such as curvature spheres,Lie curvatures,and Legendre lifts of submanifolds of S^(n)(or R^(n)),are described in *** paper also contains several important constructions of Dupin hypersurfaces with certain special properties.

关键词： Dupin hypersurfaces isoparametric hypersurfaces Lie sphere geometry Lie sphere transformations Lie curvatures