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Inverse Problems for the Dirac Operator on a Star Graph

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Acta Mathematica Sinica,English Series 2023年第1期39卷 161-175页

作者： dai Quan liu Chuan Fu YANG School of Mathematics and Statistics Nanjing University of Science and TechnologyNanjing 210094P.R.China

Following the previous work,we shall study some inverse problems for the Dirac operator on an equilateral star *** is proven that the so-called Weyl function uniquely determines the ***,we pay attention to the inverse problem of recovering the potentials from the spectral data,which consists of the eigenvalues and weight matrices,and present a constructive *** basic tool in this paper is the method of spectral mappings developed by Yurko.

关键词： Inverse problem Dirac operator on graph Weyl function weight matrix

Researching and implementation of reconfigurable Hash chip based on FPGA

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Journal of Systems Engineering and Electronics 2007年第1期18卷 183-187页

作者： Yang Xiaohui dai Zibin liu Yuanfeng Wang Ting Inst. of Electronic Technology the E L. A. Information Engineering Univ Zhengzhou 450004 ER. China

The reconfigurable cryptographic chip is an integrated circuit that is designed by means of the method of reconfigurable architecture, and is used for encryption and decryption. Many different cipher algorithms can be flexibly implemented with the aid of a reconfigurable cryptographic chip and can be used in many fields. This article takes an example for the SHA-1/224/256 algorithms, and then designs a reconfigurable cryptographic chip based on the thought and method of the reconfigurable architecture. Finally, this paper gives the implementation result based on the FPGA of the family of Stratix II of Altera Corporation, and presents a good research trend for resolving the storage in hardware implementation using FPGAs.

关键词： Reconfigurable cryptographic chip FPGA

Distribution of organochlorine pesticides (OCPs) and polychlorinated biphenyls (PCBs) in surface water and sediments from Baiyangdian Lake in North China

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Journal of Environmental Sciences 2011年第10期23卷 1640-1649页

作者： Guohua dai Xinhui liu Gang Liang Xu Han liu Shi Dengmiao Cheng Wenwen Gong State Key Laboratory of Water Environment Simulation School of Environment Beifing Normal University Beifing 100875 China

Persistent organochlorine compounds, including hexachlorocyclohexanes （HCHs）, dichlorodiphenyltrichloroethanes （DDTs） and polychlorinated biphenyls （PCBs） were analyzed in surface water and sediments from Balyangdian Lake, North China. Total concentrations of HCHs, DDTs and PCBs in surface water were in the range of 3.13-10.60, 4.05-20.59 and 19.46-131.62 ng/L, respectively, and total concentrations of HCHs, DDTs and PCBs in sediments were 1.75-5.70, 0.91-6.48 and 5.96-29.61 ng/g dry weight, respectively. Among the groups of HCHs （sum of α-HCH, β-HCH, y-HCH and 6-HCH） and DDTs （sum of DDT, DDD and DDE）, the predominance of β-HCH, DDE and DDD in water and sediment samples was clearly observed. This observation suggested that β-HCH was resistant to biodegradation and the DDTs had been transformed to its metabolites, DDE and DDD. For PCBs, penta-, hexa- and hepta-chlorinated congeners were the most abundant compounds in the both phases. Furthermore, the partitioning of chlorinated compounds between sediment and water was investigated to understand their transport and fates in aquatic ecosystems. The results indicated that average logs of organic carbon-normalized sediment-water partition coefficients （logK∝） for OCPs varied between 3.20 and 5.53, and for PCBs, logK∝ values ranged from 3.19 to 5.57. The observed logK∝ was lower than their equilibrium logK∝ predicted from linear model, which may be attributed to the solubility enhancement effect of colloidal matter in water phase and the disequilibrium between sediment and water.

关键词： oranochlorine pesticides polychlorinated biphenyls water sediment Baiyangdian Lake North China

Unthermal Hawking Radiation from a General Stationary Black Hole

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Communications in Theoretical Physics 2008年第2期49卷 379-381页

作者： ZHANG Yong-Ping dai Qian liu Wen-Biao Department of Physics Institute of Theoretical Physics Beijing Normal University Beijing 100875 China

Using Damour-Ruflini＇s method, Hawking radiation from a general stationary black hole is investigated again deeply. Considering the back reaction of the particle to the space-time and energy conservation, we find that the radiation is not exactly thermal and can take out information from the black hole. This can be used to explain the information loss paradox, and the result is consistent with the works finished before.

关键词： Hawking radiation stationary black hole back-reaction information loss paradox unitary theory

Pre-constructed SEI on graphite-based interface enables long cycle stability for dual ion sodium batteries

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Chinese Chemical Letters 2023年第7期34卷 323-326页

作者： Bao Li Bobo Cao Xinxin Zhou Zhuangzhuang Zhang Dongmei dai Mengmin Jia dai-Huo liu Collaborative Innovation Center of Henan Province for Green Manufacturing of Fine Chemicals Key Laboratory of Green Chemical Media and ReactionsMinistry of EducationSchool of Chemistry and Chemical EngineeringHenan Normal UniversityXinxiang 453007China

Lithium batteries have been widely used in all over the world for its high energy density, long-term cycle stability. While the resources of lithium metal and transition metal are limited, which restrict their applications in the grid energy storage. Dual ion sodium batteries(DISBs) possess higher energy density,especially owning high power density for its higher operating voltage(> 4.5 V). Nevertheless, the poor oxidation tolerance of carbonate electrolyte and the co-intercalation of solvents accompanied with anions are main obstacles to make the DISBs commercialization. Herein, a physical barrier(artificial SEI film) is pre-constructed in the Na||graphite batteries to solve these thorny problems. With the CSMG(covered SEI on modified graphite), batteries deliver higher capacity 40 mAh/g even under the current density of 300 mA/g and the capacity retention maintains very well after 100 cycles at a high operating ***, the function mechanism was revealed by in-situ XRD, demonstrating that the pre-constructed SEI can effectively suppress the irreversible phase transition and exfoliation of graphite, resulting from the co-intercalation of anions. Additionally, the work voltage windows of carbonate electrolyte are significantly broadened by establishing electrode/electrolyte interphase. This method opens up an avenue for the practical application of DISBs on the grid energy storage and other fields.

关键词： Dual ion sodium batteries Carbonate electrolyte High voltage Anion co-intercalation Pre-constructed SEI

Current status of surgical treatment of colorectal liver metastases

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World Journal of Clinical Cases 2018年第14期6卷 716-734页

作者： Feng Xu Bin Tang Tian-Qiang Jin Chao-liu dai Department of Hepatobiliary and Splenic Surgery Shengjing Hospital China Medical University Shenyang 110004 Liaoning Province China

Liver metastasis （LM） is one of the major causes of death in patients with colorectal cancer （CRC）. Approxi-mately 60% of CRC patients develop LM during the course of their illness. About 85% of these patients have unresectable disease at the time of presenta-tion. Surgical resection is currently the only curative treatment for patients with colorectal LM （CRLM）. In recent years, with the help of modern multimodality therapy including systemic chemotherapy, radiation therapy, and surgery, the outcomes of CRLM treatment have signifcantly improved. This article summarizes the current status of surgical treatment of CRLM including evaluation of resectability, treatment for resectable LM, conversion therapy and liver transplantation for unresectable cases, liver resection for recurrent CRLM and elderly patients, and surgery for concomitanthepatic and extra-hepatic metastatic disease （EHMD）. We believe that with the help of modern multimodality therapy, an aggressive oncosurgical approach should be implemented as it has the possibility of achieving a cure, even when EHMD is present in patients with CRLM.

关键词： Colorectal cancer Neoadjuvant therapy Liver metastasis Liver Surgery Liver transplantation Hepatectomy Laparoscopy

Effects of individual and combined additions of phosphorus,boron and cerium on primary and eutectic silicon in an Al-30Si alloy

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Rare Metals 2009年第6期28卷 651-655页

作者： dai Hongshang liu Xiangfa Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials（Ministry of Education of China） Shandong University Jinan 250061 China Shandong Binzhou Bohai Piston Co. Ltd. Binzhou 256602 China

The modification of silicon in an Al-30Si alloy was studied using optical microscopy, electron probe micro-analysis, transmission electron microscopy and differential scanning calorimetry. It is found that phosphorus master alloys combined with boron master alloys have good modification effect on primary silicon but no evident modification effect on eutectic silicon, while boron combined with cerium has good modification effect on eutectic silicon. The results of differential scanning calorimetry show that phosphorus, boron or cerium addition and their combined addition have different undercooling effects on eutectic silicon. Many scholars thought that AlP particles were the nuclei of eutectic silicon when phosphorus was enough in the alloy. Our results show that β-（Al,Si,Fe） can still be the nucleus of plate-like entectic silicon while AlP is the nucleus of primary silicon when there is enough phosphorus in the melt. In addition, the mechanism about the modification was also discussed.

关键词： Al-Si alloy eutectic silicon primary silicon modification refinement

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WOOD PERMEABILITY

Journal of Northeast Forestry University 1991年第1期2卷 91-97页

作者： Wang Jinman dai Chengyue liu YixingNortheast Forestry University 1. Northeast Forestry University China

In this paper,the permeable measurement equipment was made by *** of four species of common wood was *** species grow in northeasternarea of *** results indicated that 1)The experiment proved this equipment was reasonble instructure,good measurement precision and convenient use,and the wood permeability measurementwas satisfied.2)Wood permeability was the physical property of anisotropy in different grain *** permeability of four kinds of wood in axialis are greater than that in crosswise,thepermeability of Pinus koraiensis and Larix dahurica in radial is greater than in tangential,andthe permeability of Populus davidiana Dude and Betula playphylla Suk in tangential is greater thanthat in radial 3) According to the data of four kinds of wood permeability in different grains direc-tion,the effect mechanism on wood permeability and different properties was discussed and ana-lysed.

关键词： Physical properties of wood Wood permeability

Decomposition reaction of phosphate rock under the action of microwave plasma

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Chinese Physics B 2021年第4期30卷 361-368页

作者： Hui Zheng Meng Yang Cheng-Fa Jiang dai-Jun liu Department of Chemical Engineering Sichuan UniversityChengdu 610065China

The decomposition reaction of phosphate rock under the action of microwave plasma was *** rock and its decomposition products were characterized by x-ray diffraction(XRD),energy disperse spectroscopy(EDS),and chemical *** measurements of electron temperature(T_(e)) and electron density(N_(e)) of plasma plume under atmospheric pressure were carried out using optical emission spectroscopy(OES).The electron temperature(T_(e)) was determined based on the calculation of the relative intensity of the O Ⅱ(301.91 nm) and O Ⅱ(347.49 nm) spectral ***,electron densities were obtained using the Saha ionization equation which was based on the C Ⅰ(247.86 nm) line and the C Ⅱ(296.62 nm) line under the assumption of local thermodynamic equilibrium(LTE).The relationship between the relative intensity of the active components and the gas output was studied by the *** the reaction mechanism of the decomposition of the phosphate rock under the action of the atmospheric pressure microwave plasma was *** results showed that with the increase of CO flow and microwave power,the electron temperature and electron density in the plasma show a decreasing and increasing *** CO is dissociated into gaseous carbon ions under the action of microwave plasma,and the presence of gaseous carbon ions promotes the decomposition of the phosphate rock.

关键词： microwave plasma phosphorus decomposition optical emission spectroscopy reaction mechanism