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Study on the surface-modification of nano-hydroxyapatite with lignin and the corresponding nanocomposite with poly (lactide-co-glycolide)

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Frontiers of Chemical Science and Engineering 2021年第3期15卷 630-642页

作者： Haojie Ding Liuyun Jiang Chunyan Tang Shuo Tang bingli ma Na Zhang Yue Wen Yan Zhang Liping Sheng Shengpei Su Xiang Hu National&Local Joint Engineering Laboratory for New Petro-Chemical materials and Fine Utilization of Resources College of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China Key Laboratory of Sustainable Resources Processing and Advanced materials College of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China Key Laboratory of Chemical Biology&Traditional Chinese Medicine Research(Ministry of Education) College of Chemistry and Chemical EngineeringHunan Normal UniversityChangsha 410081China State Key Laboratory Developmental Biology of Freshwater Fish School Life ScienceHunan Normal UniversityChangsha 410081China

To obtain nano-hydroxyapatite/poly(lactideco-glycolide)(n-HA/PLGA)nanocomposite with superior mechanical properties,here,lignin was chosen to surfacemodify for n-HA through co-precipitation *** different reaction conditions of reaction time,phosphorus source,and the lignin addition amount were studied by fourier transformation infrared spectra,X-ray diffraction,the intuitionistic dispersion experiment,transmission electron microscope and thermal gravimetric *** reaction mechanism and the best appropriate reaction condition were *** importantly,the results of electromechanical universal tester,scanning electron microscope,differential scanning calorimetric analyzer,polarized optical microscopy and dynamic mechanical analysis confirmed that the obtained n-HA could greatly increase the mechanical strength of PLGA,owing to the excellent dispersion and promotion crystallization ***,in vitro cell culture experimental results indicated that the n-HA surface-modified by lignin was favorable to improve the cell biocompatibility of *** study suggested that the introduction of lignin was a novel method to acquire a highly dispersed n-HA,which would provide a new idea to achieve the n-HA/PLGA nanocomposite as bone materials in future,and it would pave the way towards a new application of lignin in biomedical field.

关键词： nanocomposite poly(lactide-co-glycolide) hydroxyapatite mechanical property

不同硅铝比两亲性HZSM-5沸石的制备和表征

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催化学报 2005年第11期26卷 956-960页

作者：马丙丽淳远须沁华董家南京大学化学化工学院介观化学教育部重点实验室江苏南京210093

采用三甲基氯硅烷并通过控制水的添加量对硅铝比分别为25,42和101的HZSM-5沸石进行外表面修饰,制得三种两亲性沸石样品.水的添加量对沸石催化剂的两亲性有显著影响.红外光谱和低温氮吸附等测试结果表明,两亲性沸石样品具有与各自母体沸... 详细信息

采用三甲基氯硅烷并通过控制水的添加量对硅铝比分别为25,42和101的HZSM-5沸石进行外表面修饰,制得三种两亲性沸石样品.水的添加量对沸石催化剂的两亲性有显著影响.红外光谱和低温氮吸附等测试结果表明,两亲性沸石样品具有与各自母体沸石相似的酸性及略小的比表面积.在环己烯水合及乙酸异戊酯水解的相界面反应中,两亲性沸石分布于水-油两相界面,并表现出明显高于各自母体沸石的催化活性.硅铝比为42的两亲性HZSM-5样品表现出最佳的相界面催化性能.相对于环己烯水合反应,两亲性HZSM-5沸石更适用于乙酸异戊酯水解的相界面催化反应.

关键词：两亲性沸石三甲基氯硅烷表面修饰 HZSM-5 相界面催化

不同孔结构两亲性沸石的制备及其对相界面反应的催化性能

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催化学报 2006年第8期27卷 737-742页

作者：马丙丽淳远须沁华董家骕南京大学化学化工学院介观化学教育部重点实验室江苏南京210093

通过三甲基氯硅烷(TMS)对沸石表面进行修饰,制得了两亲性沸石样品TMS-Hβ,TMS-HY和TMS-HZSM-5,并采用X射线衍射、红外光谱、水饱和吸附量测定和酸碱滴定等手段对改性样品进行了表征.TMS对这三种母体沸石的改性结果有所不同:对于HZSM-5沸... 详细信息

通过三甲基氯硅烷(TMS)对沸石表面进行修饰,制得了两亲性沸石样品TMS-Hβ,TMS-HY和TMS-HZSM-5,并采用X射线衍射、红外光谱、水饱和吸附量测定和酸碱滴定等手段对改性样品进行了表征.TMS对这三种母体沸石的改性结果有所不同:对于HZSM-5沸石,TMS仅在外表面修饰;对于Hβ沸石,少量TMS进入沸石孔道;而对于HY沸石,TMS则导致沸石结构部分坍塌.两亲性TMS-HZSM-5和TMS-Hβ沸石在乙酸异戊酯相界面水解反应中表现出明显优于各自母体沸石的催化性能.两亲性沸石表面硅烷基的稳定性对其催化性能有一定的影响.相对于TMS-HZSM-5沸石,TMS-Hβ沸石表面硅烷基的稳定性较强;在较高的相界面反应温度下,TMS-Hβ样品仍能维持两亲性能,表现出较高的催化活性.

关键词： Hβ沸石 HY沸石 HZSM-5沸石两亲性沸石三甲基氯硅烷相界面催化乙酸异戊酯水解异戊醇

二陈汤加减治疗慢性阻塞性肺疾病痰湿蕴肺证的临床效果

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临床研究 2024年第7期32卷 106-109页

作者：宋海燕汤金红马炳莉固始县人民医院呼吸与危重症医学科河南信阳465200

目的探讨慢性阻塞性肺疾病(COPD)痰湿蕴肺证患者采用二陈汤加减治疗的临床效果。方法选取2022年10月至2023年10月固始县人民医院收治的80例COPD痰湿蕴肺证患者,以随机数字表法分成研究组(n=40)与对照组(n=40),对照组采用常规西医治疗,... 详细信息

目的探讨慢性阻塞性肺疾病(COPD)痰湿蕴肺证患者采用二陈汤加减治疗的临床效果。方法选取2022年10月至2023年10月固始县人民医院收治的80例COPD痰湿蕴肺证患者,以随机数字表法分成研究组(n=40)与对照组(n=40),对照组采用常规西医治疗,研究组采用二陈汤加减联合常规西药治疗,比较两组临床疗效、中医证候积分、肺功能指标及炎症因子。结果研究组治疗有效率(97.50%)高于对照组(80.00%),差异具有统计学意义(P<0.05);两组治疗后各项中医证候积分均低于治疗前,且研究组低于对照组,差异均有统计学意义(P<0.05);两组治疗后肺总量(TLC)、第1秒用力呼气量(FEV_(1))、肺活量(FVC)、残气容积(RV)、潮气量(TV)均高于治疗前,且研究组高于对照组,差异均有统计学意义(P<0.05);两组治疗后干扰素-γ(IFN-γ)、内皮素-1(ET-1)水平均低于治疗前,且研究组低于对照组,差异均有统计学意义(P<0.05)。结论二陈汤加减治疗COPD痰湿蕴肺证能够提高临床疗效,改善中医证候以及肺功能,有效降低炎症因子水平。

关键词：二陈汤加减慢性阻塞性肺疾病痰湿蕴肺证临床效果

A beamforming design for weighted sidelobe power leakage minimization

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Science China(Information Sciences) 2016年第6期59卷 144-152页

作者： Cheng FENG Meng ma bingli JIAO School of Electronics Engineering and Computing Sciences Peking University

In this paper, a beamforming scheme for minimizing the weighted sidelobe power leakage while maintaining the norm of the weight vector at unity is proposed. The proposed criterion is very flexible because weighting factors are added to the sidelobes in the object function, and the weighting factors can be adjusted according to any design purpose, e.g., to minimize the interference within a direction of arrival(Do A) range. To acquire the minimum sidelobe power leakage, we first express the sidelobe power through the sidelobe coefficient matrix. Afterwards, the minimization problem can be treated as the 2-norm minimization of the sidelobe coefficient matrix. The optimal weighting vector design is then derived by singular value decomposition(SVD).Simulation results show that the proposed beamformer can decrease the sidelobe power leakage and efficiently suppress interference with barely any increase in the sidelobes; moreover, this beamforming scheme provides good robustness in consideration of the DOA mismatch.

关键词： beamforming weighted sidelobe power leakage 2-norm singular value decomposition(SVD) direction of arrival(Do A)

A Networking Solution on Uplink Channel of CoFrequency and Co-Time System

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China Communications 2016年第S2期13卷 183-188页

作者： bingli Jiao Sanjun Liu Yiming Lei Meng ma School of Electronics Engineering & Computer Science Peking University

Co-frequency and co-time full duplex(CCFD) is an attractive technology for the future wireless communication because of its high spectral ***,applications of CCFD to mobile network can suffer from strong base station to base station(B2B)*** this paper,the authors proposed a design that uses centralized base station(BS)transmit antenna and distributed BS receive antennas,each of which consists of an antennary to perform beamforming that can nullify the B2 B *** addition,we proposed a combination algorithm that uses the zero forcing method to cascade the recursive least square(RLS) method for reducing the necessary number of the bits taken to the digital *** enables the faster convergence and,thus,allows the transmission of more information bits,compared to the conventional method,for mobile *** simulation results confirm this approach for practical application.

关键词： co-frequency and co-time full duplex cellular networks beamform RLS

A High Spectral Efficiency System Enabled by Free Window with Full Duplex

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China Communications 2015年第9期12卷 93-99页

作者： Feng Cheng Cui Hongyu ma Meng Jiao bingli School of Electronics Engineering and Computer Science Peking University

This paper studies the capacity issues of a wireless communication system that implements single channel full duplex(SCFD) communication at the base station(BS), thereby the mobile stations share the channel via time division duplex(TDD). The system makes use of the same setup as has been used in previous studies of SCFD, but unlike these previous systems, the new system uses water-filling to maximize the spectral efficiency of the uplink channel. The concept of a free window is introduced to the duplex model for measuring, intuitively, the effective bandwidth of the bi-directional communication. The capacity gain is calculated and numerical results show the advantage of the proposed system over that of conventional TDD.

关键词： spectral efficiency free window time division duplex full duplex water-filling

Co-Channel Interference Suppression Techniques for Full Duplex Cellular System

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China Communications 2015年第S1期12卷 18-27页

作者： XIN Yongchao ma Meng ZHAO Zijun JIAO bingli School of Electronics Engineering and Computer Science Peking University

Co-frequency and co-time full duplex(CCFD) is a promising technique for improving spectral efficiency in next generation wireless communication systems. However, for the applications of CCFD in a cellular network, severe co-channel interference is an essential problem. Specifically, there are two significant interferences, i.e., inter-terminal interference(ITI) and inter-cell interference(ICI), which lead to an obvious performance degradation. In this paper, two techniques are proposed for suppressing the ITI and ICI in a CCFD cellular system, respectively. The first technique is obtained by modeling the three-node CCFD system as the Z-channel. After deriving the sum-capacity of the Z-channel, a sum-capacity-achieving scheme based on successive interference cancellation(SIC) is proposed. The second technique is designed by combining the fractional frequency reuse scheme with CCFD. The performance gains of the proposed two techniques in terms of signalto-interference plus noise ratio(SINR) and sumcapacity are analyzed. Simulation results show that the proposed scheme can achieve significant interference suppression performance and higher system capacity, especially for cell edge users.

关键词： co-frequency and co-time full duplex(CCFD) fractional frequency reuse(FFR) successive interference cancellation(SIC) Z-channel

Determination of estrogens and estrogenic activities in water from three rivers in Tianjin, China

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Journal of Environmental Sciences 2013年第6期25卷 1164-1171页

作者： Kaifeng Rao bingli Lei Na Li Mei ma Zijian Wang Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Institute of Environmental Pollution and Health College of Environmental and Chemical EngineeringShanghai University Key Laboratary for Biomedical Effects of Nanomaterials and Nanosafety Key Laboratory of Nuclear Analytical TechniquesInstitute of High Energy PhysicsChinese Academy of Sciences

Studies on estrogenic disrupting compounds （EDCs） occurrence and identification of main responsible compounds in river water discharged into the sea are of significance. In the present research, we screened estrogenic activities of 10 river water samples from 3 main rivers discharged into Bohai Sea in Tianjin using a recombinant two-hybrid yeast assay and chemical analysis by gas chromatography-mass spectrometry. All sample extracts induced significant estrogenic activity, with 17^-estradiol equivalents （EEQ） of raw water ranging from 5.72 to 59.06 ng/L. Six most concerned EDCs in the fiver water samples including estrone, 17（5-estradiol, 17ct-ethinylestradiol, estriol, diethylstilbestrol and estradiol valerate were determined, with their concentrations up to 50.70, 31.40, 24.40, 37.20, 2.56, and 8.47 ng/L, respectively. Through causality analysis by comparing the EEQ values of yeast assay and chemical analysis, 17ct-ethinylestradiol and 17[3-estradiol were identified as the main contributors to the estrogenic effects of the river samples, accounting for the whole estrogenic activities （62.99% to 185.66%）, and estrogen antagonistic compounds might presented in the heavy polluted water samples. The proposed approach using both chemical analysis and bioassay could be used for identification and evaluation of the estrogenic activity of EDCs in river water.

关键词： river water endocrine disrupting compounds (EDCs) yeast assay bioassay