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A light-Weight Opportunistic Forwarding Protocol with Optimized Preamble Length for Low-Duty-Cycle Wireless Sensor Networks

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Journal of Computer Science & Technology 2017年第1期32卷 168-180页

作者： Hai-Ming Chen li cui Gang Zhou Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Department of Computer Science College of William and Mary Williamsburg VA 23185 U.S.A.

In wireless sensor networks, sensed information is expected to be reliably and timely delivered to a sink in an ad-hoc way. However, it is challenging to achieve this goal because of the highly dynamic topology induced from asynchronous duty cycles and temporally and spatially varying link quality among nodes. Currently some opportunistic forwarding protocols have been proposed to address the challenge. However, they involve complicated mechanisms to determine the best forwarder at each hop, which incurs heavy overheads for the resource-constrained nodes. In this paper, we propose a light-weight opportunistic forwarding （LWOF） scheme. Different from other recently proposed opportunistic forwarding schemes, LWOF employs neither historical network information nor a contention process to select a forwarder prior to data transmissions. It confines forwarding candidates to an optimized area, and takes advantage of the preamble in low-power-listening （LPL） MAC protocols and dual-channel communication to forward a packet to a unique downstream node towards the sink with a high probability, without making a forwarding decision prior to data transmission. Under LWOF, we optimize LPL MAC protocol to have a shortened preamble （LWMAC）, based on a theoretical analysis on the relationship among preamble length, delivery probability at each hop, node density and sleep duration. Simulation results show that LWOF, along with LWMAC, can achieve relatively good performance in terms of delivery reliability and latency, as a receiver-based opportunistic forwarding protocol, while reducing energy consumption per packet by at least twice.

关键词： wireless sensor network low duty cycle low power listening opportunistic forwarding

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Preparation and Degradation Phenol Characterization of Ti/SnO_2-Sb-Mo Electrode Doped with Different Contents of Molybdenum

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Journal of Materials Science & Technology 2015年第5期31卷 473-478页

作者： Jiyan liang Cong Geng Dan li li cui Xin Wang Department of Chemical & Environmental Engineering School of ScienceShenyang University of Technology

The Ti/SnO2-Sb-Mo electrodes doped with different molar ratios of molybdenum（Mo） were prepared by sol—gel method in order to investigate the effect of Mo on the characterization of Ti/SnO2-Sb—Mo electrodes.X-ray diffraction（XRD）,field-emission scanning electron microscopy（FE-SEM）,energy dispersive spectrometry（EDS）,and linear scanning voltammetry（LSV） were used to scrutinize the coating material and the electrochemical *** concentration of phenol,the value of total organic carbon（TOC）,the mineralization current efficiency（MCE） and the ultraviolet—visible spectroscopy（UV-Vis） spectrum of phenol solution were measured over the electrochemical degradation process of phenol to confirm the phenol degradation characterization of Ti/SnO2-Sb-Mo *** showed that the electrode at the Mo content of 1 at.%provided optimal catalytic activity for phenol degradation and the longest life *** removal percentage of phenol and TOC were 99.62%and82.67%,*** Ti/SnO2-Sb-Mo electrode with 1 at.%of Mo reached maximum MCE of phenol *** kinetic investigation of phenol and TOC degradation displayed the pseudo-first order reaction *** Ti/SnO2-Sb-Mo electrode coating with 7 at.%Mo presented the highest oxygen evolution overpotential,indicating the diverse effects for different Mo molar ratio doping.

关键词： Molybdenum Antimony doped tin oxide electrode Sol-

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Microhydration of Alanine in Gas Phase Studied by Quantum Chemical Method and ABEEMσπ~/MM Fluctuating Charge Model

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Chemical Research in Chinese Universities 2013年第2期29卷 344-350页

作者： LU li-nan liU cui GONG li-dong Chemistry and Chemical Engineering Faculty Liaoning Normal University Dalian 116029 P. R. China

A fluctuating charge interaction potential function for alanine-water was constructed in the spirit of newly developed ABEEMax/MM（atom-bond electronegativity equalization method at the azc level fused into molecular mechanics）. The properties of gaseous neutral alanine-（H20）n（n=l--7） clusters were systematically investigated by quantum mechanics（QM） and the constructed ABEEMax/MM potential, such as conformations, hydrogen bonds （H-bonds）, interaction energies, charge distributions, and so on. The results of ABEEM^rrc/MM model are in fair agreement with those of QM and available experimental data. For isolated alanine, compared with those of experi- mental structure, the average absolute deviations（AAD） of bond length and bond angle are 0.002 nm and 1.4~, re- spectively. For alanine-water clusters, the AAD of interaction energies and H-bond lengths are only 3.77 kJ/mol and 0.012 nm, respectively, compared to the results of MP2/aug-cc-pVDZ//MP2/6-31 I＋G＊＊ method. The ABEEMa charges fluctuate with the changing conformation of the system, and can accurately and reasonably reflect the inter- polarization between water and alanine. The presented alanine-water potential function may provide a basis for fur- ther simulations on related aqueous solutions ofbiomolecules.

关键词： Alanine-water cluster ABEEMazc/MM fluctuating charge model Quantum chemical calculation Hydrogenbond Interaction energy

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RANDOM ANALYSIS OF HYDRODYNAMIC CHARACTERIS-TICS OF TRAJECTORY JET CAUSED BY DIFFERENT TYPES OF PIERS

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Journal of Hydrodynamics 2000年第3期12卷 34-40页

作者： cui, li Wang, Qingguo Wang, Yongtao Dalian Univ of Technology Dalian China

This paper presents some results on different tail patterns of piers with an overflow dam, and discusses in particular the hydrodynamic characteristics, the distance of water jet scour and the range of erosion area fluctuating for different parameters of average flow field when river beds are under the pressure of water jet scour caused by some special broad-tail piers. The present paper also covers some preliminary research on the relationship of movable bed tests, and introduces the method of calculating the erosion depth and area, therefore provides the best pier pattern in the construction of river beds against erosion.

关键词： Dams Erosion Hydrodynamics Jets Piers Rivers

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Changes in Volatile Compounds of Sweet Potato Tips During Fermentation

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Agricultural Sciences in China 2010年第11期9卷 1689-1695页

作者： cui li liU Chun-quan li Da-jing Institute of Farm Product Processing Jiangsu Academy of Agricultural Sciences Nanjing 210014 P.R China Engineering Research Center for Agricultural Products Processing National Agricultural Science and Technology Innovation Center in East China Nanjing 210014 P.R.China

Volatile compounds in fresh and fermented sweet potato tips at O, 10, 20, 30, and 40 d during fermentation were investigated. A new parameter named ＂relative odor activity value （ROAV）＂ was applied in evaluating the contributions of volatile compounds to flavor, considering odor threshold. The results showed that volatile compounds could be clustered in the following chemical families： alkenes （most of them were sesquiterpene）, alcohols, aldehydes, ketones, and esters in decreasing order. During fermentation, the concentrations of alkenes and ketones were increased and then decreased continuously. Alcohols and esters were increased; while the concentrations of aldehydes decreased. Interestingly, fermenting processes （0-20 d） may contribute to the increase of alkenes and ketones. Major compounds that were identified in all samples include α- and B-caryophyllene, β- and γ-elemene, and β-cubebene （in decreasing order）. The changes of their concentrations during fermentation were the same as that of alkenes. Caryophyllene was abundant in all of the samples examined. It has anti-tumour, anti-inflammatory and anti-pests activities. It can mediate interactions among plant, herbivores and their natural enemies. β- and γ-elemene, which have been used as antitumor drugs, have not been reported previously as volatiles from sweet potato tips. β-cubebene with antioxidant activity can be used as natural preservatives in food and/or by the pharmaceutical industry.

关键词： sweet potato volatile compounds fermenting sesquiterpene elemene

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Intensive follow-up vs conventional follow-up for patients with nonmetastatic colorectal cancer treated with curative intent:A metaanalysis

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World Journal of Gastrointestinal Oncology 2023年第12期15卷 2197-2211页

作者： li-li cui Shi-Qi cui Zhong Qu Zhen-Qing Ren Department of Operating Room Jiangsu Taizhou People’s HospitalTaizhou 225300Jiangsu ProvinceChina Department of Oncology Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310020Zhejiang ProvinceChina Department of Endoscopy Center Sir Run Run Shaw HospitalZhejiang University School of MedicineHangzhou 310020Zhejiang ProvinceChina Department of Nursing Jiangsu Taizhou People’s HospitalTaizhou 225300Jiangsu ProvinceChina

BACKGROUND The frequency and content of follow-up strategies remain controversial for colorectal cancer(CRC),and scheduled follow-ups have limited *** To compare intensive and conventional follow-up strategies for the prognosis of non-metastatic CRC treated with curative intent using a *** PubMed,Embase,and the Cochrane library databases were systematically searched for potentially eligible randomized controlled trials(RCTs)from inception until April *** Cochrane risk of bias was used to assess the methodological quality of the included *** hazard ratio,relative risk,and 95%confidence interval were used to calculate survival and categorical data,and pooled analyses were performed using the random-effects *** exploratory analyses were performed for sensitivity,subgroups,and publication *** Eighteen RCTs involving 8533 patients with CRC were selected for the final *** follow-up may be superior to conventional follow-up in improving overall survival,but this difference was not statistically ***,intensive follow-up was associated with an increased incidence of salvage surgery compared to conventional *** addition,there was no significant difference in the risk of recurrence between intensive and conventional follow-up strategies,whereas intensive follow-up was associated with a reduced risk of interval recurrence compared to conventional ***,the effects of intensive and conventional follow-up strategies differed when stratified by tumor location and follow-up *** Intensive follow-up may have a beneficial effect on the overall survival of patients with non-metastatic CRC treated with curative intent.

关键词： Intensive follow-up Conventional follow-up Colorectal cancer Curative intent Meta-analysis

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Analysis and implementation of new fractional-order multi-scroll hidden attractors

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Chinese Physics B 2021年第2期30卷 203-210页

作者： li cui Wen-Hui Luo Qing-li Ou Hunan University of Science and Technology Xiangtan 411201China

To improve the complexity of chaotic signals,in this paper we first put forward a new three-dimensional quadratic fractional-order multi-scroll hidden chaotic system,then we use the Adomian decomposition algorithm to solve the proposed fractional-order chaotic system and obtain the chaotic phase diagrams of different orders,as well as the Lyaponov exponent spectrum,bifurcation diagram,and SE complexity of the 0.99-order *** the process of analyzing the system,we find that the system possesses the dynamic behaviors of hidden attractors and hidden ***,we also propose a method of using the Lyapunov exponents to describe the basins of attraction of the chaotic system in the matlab environment for the first time,and obtain the basins of attraction under different order ***,we construct an analog circuit system of the fractional-order chaotic system by using an equivalent circuit module of the fractional-order integral operators,thus realizing the 0.9-order multi-scroll hidden chaotic attractors.

关键词： fractional order hidden attractor hidden bifurcation basins of attraction circuit implementation

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Ion-pair induced solvent extraction of lithium(Ⅰ)from acidic chloride solutions with tributyl phosphate

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Green Energy & Environment 2021年第4期6卷 607-616页

作者： li cui lijuan Wang Ming Feng li Fang Yanxia Guo Fangqin Cheng Institute of Resources and Environment Engineering State Environmental Protection Key Laboratory of Efficient Utilization Technology of Coal Waste ResourcesShanxi UniversityTaiyuan030006China

lithium(li)is an important energy metal in the 21st ***,the selective recovery of li is still a big challenge,especially from acidic solutions with multiple metal ions *** we report a new ion pair induced mechanism for selectively extracting li^(+)from acidic chloride solutions by tributyl phosphate(TBP).It is shown that the acidity and the chloride ions in the aqueous phase have great effects on the extraction of li^(+).The FT-IR,UV-Vis and ESI-MS experiments provide solid evidence for the formation of ion-pair complex[li(TBP)_n(H_(2)O)_(m)]^(+)[FeCl_(4)]^(-)(n-1,2,3;m-0,1)in the organic phase,which brings about the effective and efficient extraction of li^(+).This mechanism can overcome the Hofmeister bias and allow for the selective extraction of li^(+) from the extremely hydrophilic *** has also been proved that the loaded li in TBP can be effectively stripped by concentrated HCl solution with a li/Fe separation factor>*** understanding of the ion-pair transport mechanism is helpful for optimizing the recovery process or further advancing more efficient recovery techniques for li from acidic liquor.

关键词： lithium Ion-pair Tributyl phosphate Acidic chloride solution

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Synthesis and Resolution of 10,11-Dihydro-10-hydroxycyproheptadine

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Chinese Chemical Letters 2006年第4期17卷 444-446页

作者： Jian Mei cui Da li YIN Institute of Materia Medica Peking Union Medical College ＆ Chinese Academy of Medical Sciences Beijing 100050

10, 11-Dihydro-10-hydroxycyproheptadine was synthesized in a new and facile synthetic route and resolved by L-（-）-2-（1, 3）-dioxo-1, 3-dihydroisoindol-2-yl）-propionic acid and D-（＋）-tartaric acid, respectively.... 详细信息

关键词： H1 receptor antagonist, chiral center, racemate resolution, specific rotation.

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Microstructure and Martensitic Transformation Behaviors of Explosively Welded NiTi/NiTi Laminates

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Chinese Journal of Aeronautics 2007年第2期20卷 168-171页

作者： YAN Zhu cui li-shan ZHENG Yan-jun Department of Materials Science and Engineering China University of Petroleum Beijing 102249 China

The study is a first attempt to prepare bulk NiTi/NiTi shape memory alloy （SMA） laminates with a macroscopic heterogeneous composition by explosive welding and investigate their microstructures and martensitic transformation behaviors. After explosive weld- ing, a perfect interfacial bonding between the two components and a reversible martensitic transformation are realized in the tandem. Results show achievement of a fine granular structure and the maximum value of microhardness near the welding interface because of the excessive cold plastic deformation and the high impact velocity during the explosive welding. Meanwhile, the effects of aging on the transformation of the welded tandem are investigated by differential scanning calorimeter （DSC） and subject to discussion. The trans- formation temperatures of NiTi/NiTi SMAs increase with the rise of the aging temperature. The experimental results indicate the shape memory properties of NiTi/NiTi SMA fabricated by explosive welding can be improved by optimizing the aging technology.

关键词： NiTi shape memory alloy explosive welding martensitic transformation

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