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Analysis of the M~[X] /G/1 Queues with Second Multi-optional Service and Unreliable Server

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Acta Mathematicae Applicatae Sinica 2010年第3期26卷 353-368页

作者： jin-ting wang Jiang-hua Li Department of Mathematics Beijing Jiaotong University Beijing 100044 China Commanding and Engineering Institute of Chemical Defence Beijing 102205 China

A bulk-arrival single server queueing system with second multi-optional service and unreliable server is studied in this paper. Customers arrive in batches according to a homogeneous Poisson process, all customers demand the first ＂essential＂ service, whereas only some of them demand the second ＂multi-optional＂ service. The first service time and the second service all have general distribution and they are independent. We assume that the server has a service-phase dependent, exponentially distributed life time as well as a servicephase dependent, generally distributed repair time. Using a supplementary variable method, we obtain the transient and the steady-state solutions for both queueing and reliability measures of interest.

关键词： Bulk-arrival queue first essential service second optional service reliability

Discrete-time GGI/GG/1 Retrial Queues with Time-controlled Vacation Policies

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Acta Mathematicae Applicatae Sinica 2013年第4期29卷 689-704页

作者： jin-ting wang Nan wang Attahiru S.ALFA Department of Mathematics Beijing Jiaotong University Department of Electrical and Computer Engineering University of Manitoba

A discrete-time GI/G/1 retrial queue with Bernoulli retrials and time-controlled vacation policies is investigated in this paper. By representing the inter-arrival, service and vacation tlmes using a Markov-based approach, we are able to analyze this model as a level-dependent quasi-birth-and-death （LDQBD） process which makes the model algorithmically tractable. Several performance measures such as the stationary probability distribution and the expected number of customers in the orbit have been discussed with two different policies： deterministic time-controlled system and random time-controlled system. To give a comparison with the known vacation policy in the literature, we present the exhaustive vacation policy as a contrast between these policies under the early arrival system （EAS） and the late arrival system with delayed access （LAS-DA）. Significant difference between EAS and LAS-DA is illustrated by some numerical examples.

关键词： discrete queues retrial queues time-controlled vacations early and late arrival systems matrixanalytic method

Atomically precise nickel-sulfur clusters for efficient electrochemical 2,5-hydroxymethylfurfural oxidation

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Nano Research 2025年第1期18卷 140-148页

作者： Fen wang Lu-Yu Liu Sha-Sha Cui ting-ting Li Xiao-Meng Yang Zhijuan Liu Yanyong wang Henan Key Laboratory of Crystalline Molecular Functional Materials Henan International Joint Laboratory of Tumor Theranostical Cluster MaterialsGreen Catalysis Centerand College of ChemistryZhengzhou UniversityZhengzhou 450001China State Key Laboratory of Chem/Bio-sensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

Nickel sulfide exhibits excellent catalytic activity in the electrochemical 2,5-hydroxymethylfurfural oxidation reaction(HMFOR).However,due to the polydispersity of nanoparticles,it is difficult to establish a clear structure-activity relationship at the atomic *** this work,we have successfully synthesized atomically precise Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)clusters(PET:2-phenylethanethiol)for ***^(2+)and S_(2)-with atomic ratio of 1:2 was mainly existed in Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)to form Ni-S *** electrochemical test results have suggested both Ni_(6)(PET)_(12)and Ni_(4)(PET)_(8)displayed outstanding electrocatalytic ability for *** Ni_(6)(PET)_(12)exhibited better electrocatalytic ability than Ni_(4)(PET)_(8)with higher current density,lower overpotential and faster reaction *** superior electrochemical ability of Ni_(6)(PET)_(12)may be due to the enhanced adsorption towards HMF molecule with strong interaction towards hydroxyl group and furan ***,it found that the Ni^(2+)species in Ni_(6)(PET)_(12)could rapidly oxidized into Ni^(3+)species,which could spontaneously capture electron and proton from HMF for *** theoretical calculation demonstrated that the Ni_(6)(PET)_(12)process lower free energy barrier than Ni_(4)(PET)_(8)to display excellent electrocatalytic *** work is of great significance for designing efficient electrocatalysts for HMFOR.

关键词： atomically precise nickel nanoclusters 2 5-hydroxymethylfurfural electro-oxidation Ni3+species

Service Discovery in an Extensible Multifunctional XML Engine

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Service Discovery in an Extensible Multifunctional XML Engin...

CaH2-promoted activity of Ni-carbonate interface for CO2 methanation

第一届建立和谐人机环境联合学术会议（HHME2005）

作者： ZHONG ting+, jin Hao, wang Shou-Fang, WEI Kun, PAN jin-Gui (State Key Lab for Novel Software, Department of Computer Science and Technology, Nanjing University, Nanjing 210093, China)

In Pervasive Computing era, with the widespread deployment of smart devices, it is a challenge for such devices to discover various services in the network. EXgine (Extensible Multifunctional XML engi

关键词： service discovery XML pervasive computing embedded

来源： cnki会议评论

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Journal of Energy Chemistry 2025年第1期100卷 522-532页

作者： jin-Peng wang Guo-Cui Mao Hui-Lin Jiang Bao-Xia Dong Yun-Lei Teng School of Chemistry and Chemical Engineering Yangzhou University

Transition metal-carbonate interfaces often act as active sites in heterogeneous catalytic *** interface between transition metal and metal carbonate exhibits a dynamic equilibrium during the CO2hydrogenation reaction,involving surface carbonate hydrogenation and ***,there have been few reports on engineering the activity of the interface between transition metal and alkaline earth metal carbonate for catalytic *** work demonstrated that the incorporation of CaH2in Ni/CaCO3enhances the CO2methanation activity of the *** CO2conversion for Ni/CaH2-CaCO3reached 68.5%at 400°C,which was much higher than that of the Ni/CaCO3（31.6%） and Ni/CaH2-CaO （42.4%） ***,the Ni/CaH2-CaCO3catalysts remained stable during the stability test for 24 h at 400°C and 8 *** research revealed that CaH2played a crucial role in promoting the activity of the Ni-carbonate interface for ***2could modify the electronic structure of Ni and tune the structural properties of CaCO3to generate medium basic sites （OH groups）,which are favorable for the activation of H2and ***-situ Fourier transform infrared spectroscopy （FTIR） analysis combined with density functional theory calculations demonstrated that CO2activation occurs at the hydroxyl group （OH） on the CaH2-modified Ni-carbonate surface,leading to the formation of CO3H****,our study has confirmed that CO2methanation over the Ni/CaH2-CaCO3catalysts proceeds via the formate pathway.

关键词： Metal hydride Ni catalysts Carbonate Metal-carbonate interface

耐热古菌芝田硫化叶菌海藻糖生成相关酶的基因克隆、表达和序列分析

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生物化学与生物物理进展 2003年第5期30卷 798-802页

作者：吴襟于炜婷王辉刘莉王绍校张树政中国科学院微生物研究所北京100080

从耐热古菌海藻糖芝田硫化叶菌B12中分别克隆出海藻糖生成相关酶———麦芽寡糖基海藻糖合酶的基因treY和麦芽寡糖基海藻糖基水解酶的基因treZ,测定了其核苷酸序列并进行了表达.其中treY编码的蛋白质有 72 8个氨基酸、分子质量为 86ku;t... 详细信息

从耐热古菌海藻糖芝田硫化叶菌B12中分别克隆出海藻糖生成相关酶———麦芽寡糖基海藻糖合酶的基因treY和麦芽寡糖基海藻糖基水解酶的基因treZ,测定了其核苷酸序列并进行了表达.其中treY编码的蛋白质有 72 8个氨基酸、分子质量为 86ku;treZ编码的蛋白质有 5 5 9个氨基酸、分子质量为 6 5ku.它们与已报道的其他微生物的两个海藻糖生成相关酶的基因进行同源性比较,treY和treZ的同源性分别为 93%和 76 % (硫矿硫化叶菌P2)、97%和 95 % (硫矿硫化叶菌KM1)、6 3%和 6 6 % (嗜酸热硫化叶菌ATCC3390 9)、4 8%和 5 0 % (节杆菌Q36 )、4 8%和 5 2 %(根瘤菌M11)、5 0 %和 5 2 %(短杆菌).通过PHYLIP软件进行这些基因序列的分类聚类计算,获得这几种微生物间两个酶类的蛋白质系统进化树;经过氨基酸序列比较分析还发现,所有的海藻糖生成相关酶都含有糖苷酶家族 13中几个高度保守的α 淀粉酶催化活性区。

关键词：耐热古菌芝田硫化叶菌海藻糖酶基因克隆表达序列分析

The gut-eye axis:from brain neurodegenerative diseases to age-related macular degeneration

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Neural Regeneration Research 2025年第10期20卷 2741-2757页

作者： Qianzi jin Suyu wang Yujia Yao Qin Jiang Keran Li Department of Ophthalmology The Affiliated Eye Hospital of Nanjing Medical UniversityNanjingJiangsu ProvinceChina The Fourth School of Clinical Medicine Nanjing Medical UniversityNanjingJiangsu ProvinceChina

Age-related macular degeneration is a serious neurodegenerative disease of the retina that significantly impacts ***,the specific pathogenesis remains unclear,and effective early treatment options are consequently *** microbiome is defined as a large ecosystem of microorganisms living within and coexisting with a *** intestinal microbiome undergoes dynamic changes owing to age,diet,genetics,and other *** dysregulation of the intestinal flora can disrupt the microecological balance,resulting in immunological and metabolic dysfunction in the host,and affecting the development of many *** recent decades,significant evidence has indicated that the intestinal flora also influences systems outside of the digestive tract,including the ***,several studies have demonstrated the critical role of the gut-brain axis in the development of brain neurodegenerative diseases,including Alzheimer’s disease and Parkinson’s ***,the role of the“gut-eye axis”has been confirmed to play a role in the pathogenesis of many ocular ***,age-related macular degeneration and many brain neurodegenerative diseases have been shown to share several risk factors and to exhibit comparable *** such,the intestinal flora may play an important role in age-related macular *** the above context,the present review aims to clarify the gut-brain and gut-eye connections,assess the effect of intestinal flora and metabolites on age-related macular degeneration,and identify potential diagnostic markers and therapeutic ***,direct research on the role of intestinal flora in age-related macular degeneration is still relatively limited,while studies focusing solely on intestinal flora are insufficient to fully elucidate its functional role in age-related macular ***-on-a-chip technology has shown promise in clarifying the gut-eye interactions,while integrating analysis of the inte

关键词： age-related macular degeneration biological agents blinding eye disease dietary nutrition fecal microbial transplantation gut-eye axis intestinal flora metabolite microecology neurodegenerative disease

Assessing the corrosion protection property of coatings loaded with corrosion inhibitors using the real-time atmospheric corrosion monitoring technique

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International Journal of Minerals,Metallurgy and Materials 2025年第1期32卷 119-126页

作者： Xiaoxue wang Lulu jin jinke wang Rongqiao wang Xiuchun Liu Kai Gao jingli Sun Yong Yuan Lingwei Ma Hongchang Qian Dawei Zhang School of Energy and Power Engineering Beihang UniversityBeijing 100191China Beijing Institute of Space Long March Vehicle Beijing 100076China National Materials Corrosion and Protection Data Center University of Science and Technology BeijingBeijing 100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004China Shanghai Spaceflight Precision Machinery Institute Shanghai 201600China

The atmospheric corrosion monitoring(ACM)technique has been widely employed to track the real-time corrosion behavior of metal ***,limited studies have applied ACM to the corrosion protection properties of organic *** study compared a bare epoxy coating with one containing zinc phosphate corrosion inhibitors,both applied on ACM sensors,to observe their corrosion protection properties over *** with artificial damage via scratches were exposed to immersion and alternating dry and wet environments,which allowed for monitoring galvanic corrosion currents in *** the corrosion tests,the ACM currents of the zinc phosphate/epoxy coating were considerably lower than those of the blank epoxy *** trend in ACM current variations closely matched the results obtained from regular electrochemical tests and surface *** alignment highlights the potential of the ACM technique in evaluating the corrosion protection capabilities of organic *** with the blank epoxy coating,the zinc phosphate/epoxy coating showed much-decreased ACM current values that confirmed the effective inhibition of zinc phosphate against steel corrosion beneath the damaged coating.

关键词： atmospheric corrosion monitoring technology corrosion inhibitor coating carbon steel corrosion protection

Neuroprotective potential for mitigating ischemia-reperfusion-induced damage

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Neural Regeneration Research 2025年第8期20卷 2199-2217页

作者： Zi Ye Runqing Liu Hangxing wang Aizhen Zuo Cen jin Nan wang Huiqi Sun Luqian Feng Hua Yang The Clinical Medical College Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Infectious Diseases Department of Internal MedicinePeking Union Medical College HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina School of Medical Imaging Guizhou Medical UniversityGuiyangGuizhou ProvinceChina Division of Gastroenterology First Affiliated Hospital of Zhengzhou UniversityZhengzhouHenan ProvinceChina The Second Clinical Medical College Lanzhou UniversityLanzhouGansu ProvinceChina Department of Neurosurgery Affiliated Hospital of Guizhou Medical UniversityGuiyangGuizhou ProvinceChina

Reperfusion following cerebral ischemia causes both structural and functional damage to brain tissue and could aggravate a patient's condition;this phenomenon is known as cerebral ischemia-reperfusion *** studies have elucidated the neuroprotective role of the sirtuin protein family(Sirtuins)in modulating cerebral ischemia-reperfusion ***,the potential of utilizing it as a novel intervention target to influence the prognosis of cerebral ischemia-reperfusion injury requires additional *** this review,the origin and research progress of Sirtuins are summarized,suggesting the involvement of Sirtuins in diverse mechanisms that affect cerebral ischemia-reperfusion injury,including inflammation,oxidative stress,blood-brain barrier damage,apoptosis,pyroptosis,and *** therapeutic avenues related to Sirtuins that may improve the prognosis of cerebral ischemia-reperfusion injury were also investigated by modulating Sirtuins expression and affecting representative pathways,such as nuclear factor-kappa B signaling,oxidative stress mediated by adenosine monophosphate-activated protein kinase,and the forkhead box *** review also summarizes the potential of endogenous substances,such as RNA and hormones,drugs,dietary supplements,and emerging therapies that regulate Sirtuins *** review also reveals that regulating Sirtuins mitigates cerebral ischemia-reperfusion injury when combined with other risk *** Sirtuins show promise as a potential target for the treatment of cerebral ischemiareperfusion injury,most recent studies are based on rodent models with circadian rhythms that are distinct from those of humans,potentially influencing the efficacy of Sirtuinstargeting drug ***,this review provides new insights into the role of Sirtuins in the pathology and treatment of cerebral ischemia-reperfusion injury.

关键词： apoptosis autophagy blood-brain barrier dietary supplements drug hormones inflammation neuroprotection oxidative stress prognosis pyroptosis reperfusion injury risk factors RNA therapeutics