We consider the moment map m:PV_(n)→iu(n)for the action of GL(n)on V_(n)=■^(2)(C^(n))^(∗)■C^(n),and study the critical points of the functional Fn=||m||2:PV_(n)→***,we prove that[μ]∈PV_(n) is a critical point if...
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We consider the moment map m:PV_(n)→iu(n)for the action of GL(n)on V_(n)=■^(2)(C^(n))^(∗)■C^(n),and study the critical points of the functional Fn=||m||2:PV_(n)→***,we prove that[μ]∈PV_(n) is a critical point if and only if Mμ=cμI+Dμfor some cμ∈R and Dμ∈Der(μ),where m([μ])=Mμ||μ||*** we show that any algebraμadmits a Nikolayevsky derivationϕμwhich is unique up to automorphism,and if moreover,[μ]is a critical point of Fn,thenϕμ=−1 cμDμ.Secondly,we characterize the maxima and minima of the functional Fn:A_(n)→R,where A_(n) denotes the projectivization of the algebraic varieties of all the n-dimensional associative ***,for an arbitrary critical point[μ]of Fn:A_(n)→R,we obtain a description of the algebraic structure ofμ.Finally,we classify the critical points of Fn:A_(n)→R for n=2 and n=3,respectively.
In the present study,we investigated the influence of surface fluorine(F)on TiO_(2)for the photocatalytic oxidation(PCO)of ***_(2)modified with different F content was prepared and *** was found that with the increasi...
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In the present study,we investigated the influence of surface fluorine(F)on TiO_(2)for the photocatalytic oxidation(PCO)of ***_(2)modified with different F content was prepared and *** was found that with the increasing of F content,the toluene conversion rate first increased and then ***,CO_(2)mineralization efficiency showed the opposite *** on the characterizations,we revealed that F substitutes the surface hydroxyl of TiO_(2)to form the structure of≡*** presence of the appropriate amount of surface≡Ti-F on TiO_(2)greatly enhanced the separation of photogenerated carriers,which facilitated the generation of·OH and promoted the activity for the PCO of *** was further revealed that the increase of only·OH promoted the conversion of toluene to ring-containing intermediates,causing the accumulation of intermediates and then conversely inhibited the·OH generation,which led to the decrease of the CO_(2)mineralization *** above results could provide guidance for the rational design of photocatalysts for toluene oxidation.
In this study,we investigate the critical phenomena of Kerr-AdS black holes under the modified first law of ***,we considered modified black hole thermodynamics that exhibit a van der Waalslike phase *** critical expo...
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In this study,we investigate the critical phenomena of Kerr-AdS black holes under the modified first law of ***,we considered modified black hole thermodynamics that exhibit a van der Waalslike phase *** critical exponents were calculated,and then,a swallowtail diagram of free energy was *** with existing results,the main difference is the correspondence between the thermal quantities of Kerr-AdS black holes and the van der Waals *** a previous study[***,***,and ***,***.D 85044005(2012)],the correspondence was(Ω_(H),J)→(V,P),while in our study,the correspondence was(J,Ω_(H))→(V,P).This difference was owing to the rotating *** modified black hole thermodynamics were associated with rotating *** free energy in such a reference contains extra rotating energy,which induces a Legendre transformation in the(Ω_(H),J)cross-section,causing the difference in correspondence.
Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyt...
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Lithium metal batteries(LMBs)are emerging as a promising energy storage solution owing to their high energy density and specific ***,the non-uniform plating of lithium and the potential rupture of the solid-electrolyte interphase(SEI)during extended cycling use may result in dendrite growth,which can penetrate the separator and pose significant short-circuit *** a stable SEI is essential for the long-term operation of the ***-rich SEI has garnered significant attention for its ability to effectively passivate electrodes,regulate lithium deposition,and inhibit electrolyte *** the structural components and preparation methods of existing fluorinated SEI is crucial for optimizing lithium metal anode *** paper reviews the research on optimizing LiF passivation interfaces to protect lithium metal *** focuses on four types of compositions in fluorinated SEI that work synergistically to enhance SEI *** instance,combining compounds with LiF can further enhance the mechanical strength and ionic conductivity of the *** metals with LiF significantly improves electrochemical performance at the SEI/anode interface,with a necessary focus on reducing electron tunneling ***,incorporating polymers with LiF offers balanced improvements in interfacial toughness and ionic conductivity,though maintaining structural stability over long cycles remains a critical area for future *** alloys combined with LiF increase surface energy and lithium affinity,challenges such as dendrite growth and volume expansion *** summary,this paper emphasizes the crucial role of interfacial structures in LMBs and offers comprehensive guidance for future design and development efforts in battery technology.
The behaviors of unsteady flow structures and corresponding hydrodynamics for a pitching hydrofoil are investigated numerically and theoretically in the present *** aims are to derive the total lift by finite-domain i...
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The behaviors of unsteady flow structures and corresponding hydrodynamics for a pitching hydrofoil are investigated numerically and theoretically in the present *** aims are to derive the total lift by finite-domain impulse theory for subcavitating flow(σ=8.0)and cavitating flow(σ=3.0),and to quantify the distinct impact of individual vortex structures on the transient lift to appreciate the interplay among cavitation,flow structures,and vortex *** motion of the hydrofoil is set to pitch up clockwise with an almost constant rate from 0°to 15°and then back to 0°,for the Reynolds number,7.5×105,and the frequency,0.2 Hz,*** results reveal that the presence of cavities delays the migration of the laminar separation bubble(LSB)from the trailing edge(TE)to the leading edge(LE),consequently postponing the hysteresis in the inflection of lift *** eventual stall under the sub-cavitation regime is the result of LSB *** the instabilities within the leading-edge LSB induce the convection of cavitation-dominated vortices under the cavitation regime *** validated the lift coefficients on the hydrofoil through the finite-domain impulse theory using the standard force expression,the Lamb vector integral emerges as the main contribution to the generation of unsteady ***,the typical vortices’contributions to the transient lift during dynamic stall are accurately *** analysis indicates that the clockwise leading-edge vortex(−LEV)contributes positively,while the counterclockwise trailing-edge vortex(+TEV)contributes *** negative influence becomes particularly pronounced after reaching the peak of total lift,as the shedding of the concentrated wake vortex precipitates a sharp decline due to a predominant negative lift contribution from the TEV ***,the vortices’contribution is relatively modest in sub-cavitating flow,but it is notably more significant in the context of incipient ca
Objective To investigate the outcome of revised super-long down-regulation protocol （RSDP） for in vitro fertilization / intracytoplasmic sperm injection-embryo transfer （1VF/1CS1-ET） in the special infertile pat...
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Objective To investigate the outcome of revised super-long down-regulation protocol （RSDP） for in vitro fertilization / intracytoplasmic sperm injection-embryo transfer （1VF/1CS1-ET） in the special infertile patients with repeated implantation failure （RIF）. Methods Patients with RIF were divided into RSDP group and routine long downregulation protocol （RLDP） group. In RSDP group, gonadotropin releasing hormone agonist （GnRHa） was injected intramuscularly by 2.5 mg in mid-luteal phase for the ftrst time and 1.25 mg after 28 d; gonadotropin （Gn） was started 14 d later after the second GnRHa dose. IVF/ICSI-ET was performed according to the routine procedure. The clinical outcomes of RSDP group were compared with those of RLDP group. Results In RSDP group, the number of retrieved oocytes and valid embryos was significantly lower （P〈0.05）; there were no significant differences about fertilization rate （P〉0. 05）; both good-quality embryo rate and implantation rate were significantly increased （P〈0. 005）; clinical pregnancy rate was obviously improved （P〈0. 05）, as compared with RLDP *** RSDP can improve the IVF outcomes significantly in RIF patients.
To enhance the high-temperature oxidation resistance and mechanical properties of a secondgeneration nickel-based superalloy,various concentrations of lanthanum(La)ranging from 5.0×10^(-5)wt.%to 3.4×10^(-4)wt.%are a...
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To enhance the high-temperature oxidation resistance and mechanical properties of a secondgeneration nickel-based superalloy,various concentrations of lanthanum(La)ranging from 5.0×10^(-5)wt.%to 3.4×10^(-4)wt.%are added to the *** microstructure of the nickel-based single crystal superalloy with trace of La was examined by means of SEM,EDS and *** show the addition of La decreases the segregation of elements and increases the amount ofγ/γ′eutectics of the as-cast alloy,and in the interdendritic region,the growth of eutectics is accompanied by the growth of strip clusters composed of Ni_(5)La and Ni_(3)*** the La content in the alloy increases,the proportion of Ni_(5)La in the cluster *** heat treatment,incipient melting occurs in the cluster regions,leading to an increase in microporosity compared to the original as-cast ***,the heat treatment alters the shape of the clusters from a strip morphology to an elliptical one,and it changes their composition from Ni_(5)La and Ni_(3)Ta to a combination of Ni_(5)La,Ni_(3)Ta,and MC carbides.
High-entropy materials have become high-activity electrocatalysis owing to their high-entropy effect and multiple active ***,we synthesize a series of carbon-supported nano high-entropy oxides(HEOs/C),specifically (Pt...
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High-entropy materials have become high-activity electrocatalysis owing to their high-entropy effect and multiple active ***,we synthesize a series of carbon-supported nano high-entropy oxides(HEOs/C),specifically (PtFeCoNiCu)O/C,using a carbothermal shock (CTS) method for application as a cathode catalyst in direct borohydride fuel cells (DBFCs).The microstructure of the prepared catalysts was characterized by X-ray photoelectron spectroscopy,X-ray absorption fine structure,and transmission electron *** prepared (PtFeCoNiCu)O/C,with particle sizes ranging from 2 to 4 nm,demonstrates 3.94 transferred electrons towards the oxygen reduction reaction in an alkaline environment,resulting in a minimal H_(2)O_(2)yield of 2.6%.Additionally,it exhibits a Tafel slope of 61 mV dec-1,surpassing that of commercial Pt/C (82 mV dec-1).Furthermore,after 40,000 cycles of cyclic voltammetry(CV) testing,the half-wave potential of (PtFeCoNiCu)O/C shows a positive shift of 3 mV,with no notable decline in the limiting current *** (PtFeCoNiCu)O/C is used as a cathode catalyst in DBFCs,the DBFC achieves a maximum power density of 441 mW cm^(-2)at 60°C and sustains a cell voltage of approximately 0.73 V after 52 h at 30°*** findings confirm that HEO/C is a promising cathode catalyst for DBFCs.
Despite ongoing advancements in cancer treatment,the emergence of primary and acquired resistance poses a significant challenge for both traditional chemotherapy and immune checkpoint blockade *** demand for targeted ...
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Despite ongoing advancements in cancer treatment,the emergence of primary and acquired resistance poses a significant challenge for both traditional chemotherapy and immune checkpoint blockade *** demand for targeted therapeutics for multidrug-resistant cancer is more important than ***,as emerging alternatives to current anticancer drugs,offer exquisite versatility in facilitating the design of novel oncology drugs,with the core superiorities of good biocompatibility and a low tendency to induce drug *** review comprehensively introduces the pharmacological mechanisms of peptide-based drugs and strategies for overcoming multidrug resistance(MDR)in cancers,including inducing cell membrane lysis,targeting organelles,activating anticancer immune responses,enhancing drug uptake,targeting ATP-binding cassette(ABC)transporters,and targeting B-cell lymphoma-2(BCL-2)family ***,the current clinical applications of representative peptides in combating MDR cancers and their potential directions for medicinal chemistry research have been thoroughly *** review offers essential insights into the novel treatment approaches for MDR cancers and highlights the trends and perspectives in this field.
It is of great significance to accurately and rapidly identify shale lithofacies in relation to the evaluation and prediction of sweet spots for shale oil and gas reservoirs. To address the problem of low resolution i...
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It is of great significance to accurately and rapidly identify shale lithofacies in relation to the evaluation and prediction of sweet spots for shale oil and gas reservoirs. To address the problem of low resolution in logging curves, this study establishes a grayscale-phase model based on high-resolution grayscale curves using clustering analysis algorithms for shale lithofacies identification, working with the Shahejie Formation, Bohai Bay Basin, China. The grayscale phase is defined as the sum of absolute grayscale and relative amplitude as well as their features. The absolute grayscale is the absolute magnitude of the gray values and is utilized for evaluating the material composition(mineral composition + total organic carbon) of shale, while the relative amplitude is the difference between adjacent gray values and is used to identify the shale structure type. The research results show that the grayscale phase model can identify shale lithofacies well, and the accuracy and applicability of this model were verified by the fitting relationship between absolute grayscale and shale mineral composition, as well as corresponding relationships between relative amplitudes and laminae development in shales. Four lithofacies are identified in the target layer of the study area: massive mixed shale, laminated mixed shale, massive calcareous shale and laminated calcareous shale. This method can not only effectively characterize the material composition of shale, but also numerically characterize the development degree of shale laminae, and solve the problem that difficult to identify millimeter-scale laminae based on logging curves, which can provide technical support for shale lithofacies identification, sweet spot evaluation and prediction of complex continental lacustrine basins.
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