鄂尔多斯盆地东缘上古生界致密储层含气系统压力演化

鄂尔多斯盆地东缘上古生界多层系致密气发育,准确认识气藏压力演化过程对深化致密气成藏认识和实现气井高产稳产具有指导意义。综合应用钻测井资料和岩心流体包裹体测试,结合盆地埋藏史和热演化史模拟,揭示了鄂尔多斯盆地东缘上古生界含气系统压力演化。结果显示,研究区自下而上发育欠压、略微欠压和常压系统。均一温度和盐度总体上连续分布,反映了油气连续充注过程。太原组、山西组和下石盒子组均一温度和盐度正相关,反映近源生烃后快速充注;上石盒子组和石千峰组均一温度和盐度负相关,受流体远距离运移充注和紫金山构造热事件作用下的气藏再平衡影响。研究区在白垩纪中期大量生烃,形成了异常高压,储层压力在34.89~38.26 MPa。后期地层抬升造成储层压力降低,其中地层降温贡献了50.31%~57.85%;天然气膨胀引起的气体运移贡献了28.25%~41.95%,且以上部地层降低为主;孔隙反弹贡献了0.37%~0.79%。相关成果系统揭示了上古生界致密气藏压力系统演化及现今气藏压力成因,对于认识鄂尔多斯盆地和类似盆地致密气富集成藏规律具有借鉴意义。

多天线频谱共享CR-NOMA系统安全中断性能分析

认知无线电(CR)非正交多址接入(NOMA)网络(记为CR-NOMA)已是无线通信领域的研究热点之一。由于无线信道的开放性,使得无线网络的安全通信成为当前急需解决的问题。该文研究了频谱共享多天线CR-NOMA网络安全中断性能,首先分析了最优天线选择(OAS)方案的安全中断概率(SOP),并推导了其精确的闭合表达式。其次,分析了空时传输(STT)方案的SOP,并推导了其精确的闭合表达式。最后,对次用户两种方案的SOP渐近性能进行了分析,揭示了系统参数对SOP的影响。最后,采用Monte Carlo仿真验证了理论分析的正确性。研究发现,两种方案基站分别存在一个最优峰值发射功率,使得远距离次用户的安全中断性能最佳。仿真结果表明增大基站峰值发射功率,OAS方案的近距离次用户的SOP会始终优于STT方案,远距离次用户的SOP会劣于STT方案。

处理走航式海洋多参数剖面测量系统(MVP)温度和电导率滞后效应的方法

走航式海洋多参数剖面测量系统(moving vessel profiler,MVP)是一种集成程度和自动化程度都较高的海洋调查设备,能对海洋多要素进行同时观测,获得水平方向的高分辨率数据资料。由于温度和电导率传感器响应时间的不匹配,MVP下放速度过快(峰值速度4 m/s)而造成非常明显的盐度尖峰现象。本研究结合Fofonoff(F)法、时间常数指数递归数字滤波(Giles and McDougall,GM)法和Grose提出的盐度尖峰订正方案,提出了一种新的方法,即MCT(match conductivity and temperature response time)法,通过对压力、温度和电导率传感器进行响应时间的匹配来减弱盐度尖峰。将SBE-9型CTD资料作为标准,发现订正后的资料与CTD盐度曲线的互相关系数为0.917,误差比订正前减小80%。对比35°N断面修正前后的盐度资料,订正后温盐跃层处出现的低盐区域消失。MVP的应用比常规海洋调查仪器CTD对于海洋现象的观测更有优势。

Boehmeria nivea var. strigosa (Urticaceae), a new variety from Southwest China

Boehmeria nivea var.strigosa Zeng Y.Wu&Y.Zhao,a new variety of B.nivea(Urticaceae)from Southwest China,is here described based on evidence from morphology and molecular phylogeny.This new variety is mainly characterized by its green abaxial leaf blade,partly connate stipules,and densely patent strigose hairs on stems and potioles.The phylogenetic analysis based on rbc L,nrDNA and rbc L+nrDNA datasets,revealed that all individuals of B.nivea var.strigosa formed a monophyletic group.The conservation status of B.nivea var.strigosa is assessed as“Near Threatened”(NT)according to IUCN evaluation criteria.The discovery of this new variety is not only crucial for the taxonomy of ramie,but also provides reference for the exploration and utilization of ramie.

OFDI对中国就业影响的产业异质性研究——基于广义虚拟经济视角的系统GMM分析

将国民经济划分为广义虚拟经济和实体经济两大产业部类,结合我国2004-2013年18个行业的动态面板数据,运用系统GMM方法和联立方程模型实证分析两大产业部类的OFDI对就业的影响。研究发现,相较于实体经济,广义虚拟经济OFDI通过国内资本形成路径对就业的补充效应更为显著,通过逆向技术外溢对就业的替代效应更小;无论是直接、间接还是总效应,广义虚拟经济OFDI的就业效应明显大于实体经济。

Research on pumped storage and complementary energy development models for abandoned mines in China

Within the framework of achieving carbon neutrality,various industries are confronted with fresh challenges.The ongoing process of downsizing coal industry operations has evolved into a new phase,with the burgeoning proliferation of abandoned mines posing a persistent issue.Addressing the challenges and opportunities presented by these abandoned mines,this paper advocates for a scientific approach centered on the advancement of pumped storage energy alongside gas-oil complementary energy.Leveraging abandoned mine tunnels to establish pumped storage power stations holds significant ecological and economic importance for repurposing these sites.This initiative not only serves as an effective means to restore the ecological balance in mining regions but also provides an environmentally friendly approach to repurposing abandoned mine tunnels,offering a blueprint for economically viable pumped storage power stations.This article delineates five crucial scientific considerations and outlines seven primary models for the utilization of abandoned mine sites,delineating a novel,comprehensive pathway for energy and power development that emphasizes multi-energy complementarity and synergistic optimization within abandoned mines.

Chrysosplenium fallax Koldaeva(Chrysosplenium),a newly recorded species from China

Chrysosplenium fallax Koldaeva,recently discovered and collected in Yanji,Jilin Province,repre-sents a newly recorded species of Saxifragaceae in China.This species,native to the Russian Far East,was first described as a new species in 2021.Based on precise field investigations and specimen examination,we provide a comprehensive description of C.fallax and its seed micromorphology.Phylogenetic analysis based on chloroplast genomes of 45 Chrysosplenium species confirmed the systematic position of C.fallax in Chrysosplenium.Voucher specimens were deposited in the Herbarium of South-Central Minzu University(HSN).

Evolutionary analysis of green credit and automobile enterprises under the mechanism of dynamic reward and punishment based on government regulation

To explore the green development of automobile enterprises and promote the achievement of the“dual carbon”target,based on the bounded rationality assumptions,this study constructed a tripartite evolutionary game model of gov-ernment,commercial banks,and automobile enterprises;introduced a dynamic reward and punishment mechanism;and analyzed the development process of the three parties’strategic behavior under the static and dynamic reward and punish-ment mechanism.Vensim PLE was used for numerical simulation analysis.Our results indicate that the system could not reach a stable state under the static reward and punishment mechanism.A dynamic reward and punishment mechanism can effectively improve the system stability and better fit real situations.Under the dynamic reward and punishment mechan-ism,an increase in the initial probabilities of the three parties can promote the system stability,and the government can im-plement effective supervision by adjusting the upper limit of the reward and punishment intensity.Finally,the implementa-tion of green credit by commercial banks plays a significant role in promoting the green development of automobile enter-prises.

Bifurcation and Stability Analysis of Time-Delayed Wheelset System under White Noise Excitation

Considering the impact of time delay in the lateral stiffness of the primary suspension and stochastic disturbances of equivalent conicity on the wheelset system, a stochastic time-delayed wheelset system is established. The wheelset system is transformed into a onedimensional Ito stochastic differential equation using central manifold and stochastic averaging methods. The analysis of the system's stochastic stability is conducted through the maximum Lyapunov exponent and singular boundary theory. The combination of the stationary probability density method and numerical simulation is employed to discuss the types and conditions of stochastic P-bifurcation in the wheelset system. The results indicate that changes in speed and time delay induce stochastic P-bifurcations in the wheelset system, while changes in noise intensity do not lead to stochastic P-bifurcations. Both time delay and equivalent conicity affect the critical speed of the wheelset system, and the critical speed gradually increases with the decrease of time delay and equivalent conicity.

Teffichthys wui sp. nov., a new perleidid fish from the Early Triassic of Jiangsu and Anhui, China

Perleididae is a group of stem neopterygian fishes known only from the Triassic.Here,we report the discovery of a new perleidid,Teffichthys wui sp.nov.,based on six well-preserved specimens from the late Smithian(Olenekian,Early Triassic)marine deposits of Jurong,Jiangsu and Chaohu,Anhui,China.This new discovery documents the third and youngest species of Teffichthys,which is slightly younger than the Dienerian(Induan)T.elegans from Guizhou and the early Smithian T.madagascariensis from Madagascar.The new species shows diagnostic features of Teffichthys(presence of a spiracular,38-41 lateral line scales,and no more than three epaxial rays in the caudal fin)but differs from T.madagascariensis and T.elegans in some autapomorphies(e.g.,a horizontal opercle/subopercle contact and smooth scales with a nearly straight posterior margin).The diagnostic features for the genus Teffichthys and the family Perleididae are emended based on detailed comparisons of the new taxon with other perleidids.The phylogenetic relationships of perleidids with other stem neopterygians are discussed using a cladistic approach,and the results provide new insights into the phylogeny and classification of main stem neopterygian clades.

A review of Vietanna(Hemiptera:Cicadidae)with descriptions of two new species from China

The cicada genus Vietanna is reviewed based on the descriptions of two new species,V.perparva sp.nov.and V.longiloba sp.nov.,from China.The relationship of this genus to related taxa is discussed based on the phylogeny of Vietanna and representative species from subtribes Puranina,Leptopsaltriina,Euterpnosiina and Leptosemiina based on the mitochondrial gene COI and nuclear genes EF-1αand ARD1.

Development and Therapeutic Applications of Precise Gene Editing Technology

The advent of gene editing represents one of the most transformative breakthroughs in life science,making genome manipulation more accessible than ever before.While traditional CRISPR/Cas-based gene editing,which involves double-strand DNA breaks(DSBs),excels at gene disruption,it is less effective for accurate gene modification.The limitation arises because DSBs are primarily repaired via non-homologous end joining(NHEJ),which tends to introduce indels at the break site.While homology directed repair(HDR)can achieve precise editing when a donor DNA template is provided,the reliance on DSBs often results in unintended genome damage.HDR is restricted to specific cell cycle phases,limiting its application.Currently,gene editing has evolved to unprecedented levels of precision without relying on DSB and HDR.The development of innovative systems,such as base editing,prime editing,and CRISPR-associated transposases(CASTs),now allow for precise editing ranging from single nucleotides to large DNA fragments.Base editors(BEs)enable the direct conversion of one nucleotide to another,and prime editors(PEs)further expand gene editing capabilities by allowing for the insertion,deletion,or alteration of small DNA fragments.The CAST system,a recent innovation,allows for the precise insertion of large DNA fragments at specific genomic locations.In recent years,the optimization of these precise gene editing tools has led to significant improvements in editing efficiency,specificity,and versatility,with advancements such as the creation of base editors for nucleotide transversions,enhanced prime editing systems for more efficient and precise modifications,and refined CAST systems for targeted large DNA insertions,expanding the range of applications for these tools.Concurrently,these advances are complemented by significant improvements in in vivo delivery methods,which have paved the way for therapeutic application of precise gene editing tools.Effective delivery systems are critical for the success of gene therapies,and recent developments in both viral and non-viral vectors have improved the efficiency and safety of gene editing.For instance,adeno-associated viruses(AAVs)are widely used due to their high transfection efficiency and low immunogenicity,though challenges such as limited cargo capacity and potential for immune responses remain.Non-viral delivery systems,including lipid nanoparticles(LNPs),offer an alternative with lower immunogenicity and higher payload capacity,although their transfection efficiency can be lower.The therapeutic potential of these precise gene editing technologies is vast,particularly in treating genetic disorders.Preclinical studies have demonstrated the effectiveness of base editing in correcting genetic mutations responsible for diseases such as cardiomyopathy,liver disease,and hereditary hearing loss.These technologies promise to treat symptoms and potentially cure the underlying genetic causes of these conditions.Meanwhile,challenges remain,such as optimizing the safety and specificity of gene editing tools,improving delivery systems,and overcoming off-target effects,all of which are critical for their successful application in clinical settings.In summary,the continuous evolution of precise gene editing technologies,combined with advancements in delivery systems,is driving the field toward new therapeutic applications that can potentially transform the treatment of genetic disorders by targeting their root causes.

Effects of pooling,specialization,and discretionary task completion on queueing performance

Pooling,unpooling/specialization,and discretionary task completion are typical operational strategies in queueing systems that arise in healthcare,call centers,and online sales.These strategies may have advantages and disadvantages in different operational environments.This paper uses the M/M/1 and M/M/2 queues to study the impact of pooling,specialization,and discretionary task completion on the average queue length.Closed-form solutions for the average M/M/2 queue length are derived.Computational examples illustrate how the average queue length changes with the strength of pooling,specialization,and discretionary task completion.Finally,several conjectures are made in the paper.

Research on Automatic Test System of Engine Blade Natural Frequency

Blades are one of the important components on aircraft engines.If they break due to vibration failure,the normal operation of the entire engine will be offected.Therefore,it is necessary to measure their natural frequency before installing them on the engine to avoid resonance.At present,most blade vibration testing systems require manual operation by operators,which has high requirements for operators and the testing process is also very cumbersome.Therefore,the testing efficiency is low and cannot meet the needs of efficient testing.To solve the current problems of low testing efficiency and high operational requirements,a high-precision and high-efficiency automatic test system is designed.The testing accuracy of this system can reach ±1%,and the testing efficiency is improved by 37% compared to manual testing.Firstly,the influence of compression force and vibration exciter position on natural frequency test is analyzed by amplitude-frequency curve,so as to calibrate servo cylinder and fourdimensional motion platform.Secondly,the sine wave signal is used as the excitation to sweep the blade linearly,and the natural frequency is determined by the amplitude peak in the frequency domain.Finally,the accuracy experiment and efficiency experiment are carried out on the developed test system,whose results verify its high efficiency and high precision.

Higher-order mode analysis for SOLEIL-type superconducting cavity

A 499.8 MHz SOLEIL-type superconducting cavity was simulated and designed for the first time in this paper.The higher-order mode(HOM)properties of the cavity were investigated.Two kinds of coaxial HOM couplers were designed.Using 4 L-type and 4 T-type HOM couplers,the longitudinal impedance and the transverse impedances were suppressed to below 3 kΩand 30 kΩ/m,respectivly.The HOM damping requirements of Hefei Advanced Light Facility(HALF)were satisfied.This paper conducted an in-depth study on the radio frequency(RF)design,multipacting optimization,and thermal analysis of these coaxial couplers.Simulation results indicated that under operating acceleration voltage,the optimized couplers does not exhibit multiplicating or thermal breakdown phenomena.The cavity has the potential to reach a higher acceleration gradient.

Model Order Reduction Methods for Discrete Systems via Discrete Pulse Orthogonal Functions

This paper explores model order reduction(MOR)methods for discrete linear and discrete bilinear systems via discrete pulse orthogonal functions(DPOFs).Firstly,the discrete linear systems and the discrete bilinear systems are expanded in the space spanned by DPOFs,and two recurrence formulas for the expansion coefficients of the system’s state variables are obtained.Then,a modified Arnoldi process is applied to both recurrence formulas to construct the orthogonal projection matrices,by which the reduced-order systems are obtained.Theoretical analysis shows that the output variables of the reducedorder systems can match a certain number of the expansion coefficients of the original system’s output variables.Finally,two numerical examples illustrate the feasibility and effectiveness of the proposed methods.

A new genus of galeaspids(jawless stem-Gnathostomata)from the early Silurian Chongqing Lagerstätte,China

The early Silurian Chongqing Lagerstätte(middle Telychian)yields exceptionally preserved articulated jawless and jawed fishes.Here,we describe a new eugaleaspiform(Galeaspida,jawless stem-Gnathostomata),Miaojiaaspis dichotomus gen.et sp.nov.,from the Chongqing Lagerstätte in Xiushan,Chongqing,China.The new form resembles Tujiaaspis vividus in the short medial dorsal canal,and the presence of the branching ends of the lateral transverse canal.They differ in that T.vividus has highly developed subordinate branches of the sensory canals that form a reticulate sensory canal system,and the median dorsal opening is more elongated.Our phylogenetic analysis recovers M.dichotomus and T.vividus as a monophyletic clade(Tujiaaspidae fam.nov.),which is supported by two synapomorphies:the short medial dorsal canal,and the branching ends of the lateral transverse canal.Tujiaaspidae forms a trichotomy with Shuyuidae and a clade comprising Anjiaspis,Sinogaleaspidae,Yongdongaspidae,and the‘eugaleaspid cluster’.The sensory canal patterns in galeaspids are compared to show the transformation sequence of the sensory canal system in Eugaleaspiformes.

Conjugated microporous polymers-scaffolded enzyme cascade systems with enhanced catalytic activity

Enhancing catalytic activity of multi-enzyme in vitro through substrate channeling effect is promis-ing yet challenging.Herein,conjugated microporous polymers(CMPs)-scaffolded integrated en-zyme cascade systems(I-ECSs)are constructed through co-entrapping glucose oxidase(GOx)and horseradish peroxidase(HRP),in which hydrogen peroxide(H_(2)O_(2)) is the intermediate product.The interplay of low-resistance mass transfer pathway and appropriate pore wall-H_(2)O_(2) interactions facilitates the directed transfer of H_(2)O_(2),resulting in 2.4-fold and 5.0-fold elevation in catalytic activ-ity compared to free ECSs and separated ECSs,respectively.The substrate channeling effect could be regulated by altering the mass ratio of GOx to HRP.Besides,I-ECSs demonstrate excellent stabili-ties in harsh environments and multiple recycling.

Short-term prediction of photovoltaic power generation based on LMD-EE-ESN with error correction

Considering the instability of the output power of photovoltaic(PV)generation system,to improve the power regulation ability of PV power during grid-connected operation,based on the quantitative analysis of meteorological conditions,a short-term prediction method of PV power based on LMD-EE-ESN with iterative error correction was proposed.Firstly,through the fuzzy clustering processing of meteorological conditions,taking the power curves of PV power generation in sunny,rainy or snowy,cloudy,and changeable weather as the reference,the local mean decomposition(LMD)was carried out respectively,and their energy entropy(EE)was taken as the meteorological characteristics.Then,the historical generation power series was decomposed by LMD algorithm,and the hierarchical prediction of the power curve was realized by echo state network(ESN)prediction algorithm combined with meteorological characteristics.Finally,the iterative error theory was applied to the correction of power prediction results.The analysis of the historical data in the PV power generation system shows that this method avoids the influence of meteorological conditions in the short-term prediction of PV output power,and improves the accuracy of power prediction on the condition of hierarchical prediction and iterative error correction.

Local existence and uniqueness of solutions to the evolutionary model for magnetoviscoelasticity

In this paper,we prove the local existence and uniqueness of solutions to the evolutionary model for magnetoviscoelasticity in R^(2),R^(3).This model consists of an incompressible Navier-Stokes,a regularized system for the evolution of the deformation gradient and the Landau-Lifshitz-Gilbert system for the dynamics of the mag-netization.Our approach depends on approximating the system with a sequence of perturbed systems.