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A new method for removing mixed noises

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science China(Information sciences) 2011年第1期54卷 51-59页

作者： LI Bing1,3,LIU QuanSheng1,2,XU JiaWei1 & LUO XiaoJun1 1School of Mathematics and Computation science,Changsha University of science&Technology, Changsha 410076,China 2LMAM,Université de Bretagne-Sud,Campus de Tohannic,Vannes 56017.Université Européenne de Bretagne,France 3Department of Mathematics,Zhongshan Polytechnic,Zhongshan 528404,China School of Mathematics and Computation science Changsha University of Science & Technology Changsha China Department of Mathematics Zhongshan Polytechnic Zhongshan China LMAM Université de Bretagne-Sud Vannes France Université Européenne de Bretagne Bretagne France

We first introduce a similarity assumption to describe the similarity phenomenon in natural images, and establish a similarity principle which supplies a simple mathematical justification for the non-local means filter in removing Gaussian noises.Using the similarity principe in an adapted way,we then propose a new algorithm,called mixed noise filter(MNF)to remove simultaneously a mixture of Gaussian and random impulse noises.Our experiments show that our new filter improves significantly the trilateral filter in removing mixed noises,and that it is as effcient as the non-local means filter in removing Gaussian noises,and as good as the trilateral filter in removing random impulse noises.

关键词： mixed noises Gaussian noises random impulse noises image restoration nonlinear filters trilateral filter non-local means filter denoising similarity principle

缺陷g-CN优化催化层的磷酸分布以提高高温质子膜燃料电池的性能(英文)

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science China Materials 2023年

作者：张东材孔志杰黄根杜石谦林嘉祺王燕勇余刚陶李王双印 State Key Laboratory of Chem/Bio-Sensing and Chemometrics Provincial Hunan Key Laboratory for Graphene Materials and Devices College of Chemistry and Chemical Engineering the National Supercomputer Centers in Changsha Hunan University Shenzhen Research Institute Hunan University

磷酸作为质子传导介质对于高温质子膜燃料电池是至关重要的,但调节磷酸分布来减少电催化剂中毒及保持高反应性的稳定性仍面临挑战.在本工作中,缺陷g-C3N4被分散到Pt/C催化层中促进磷酸的分布来提高催化剂的本征活性表达.由于缺陷g-C3N4...

磷酸作为质子传导介质对于高温质子膜燃料电池是至关重要的,但调节磷酸分布来减少电催化剂中毒及保持高反应性的稳定性仍面临挑战.在本工作中,缺陷g-C3N4被分散到Pt/C催化层中促进磷酸的分布来提高催化剂的本征活性表达.由于缺陷g-C3N4修饰,低铂负载量在阳极(0.20 mgPtcm-2)和阴极(0.40 mgPtcm-2)条件下,高温质子膜燃料电池呈现一个高的峰功率672 mW cm-2和高反应性(高于620 mW cm-2),且具有3500个加速循环的优越稳定性,该性能优于目前报道的结果.本工作首次揭示了缺陷g-C3N4与磷酸的酸碱相互作用可调节催化层的磷酸分布,从而提高催化剂的本征活性表达和利用率.

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Synthesis of single crystal-like hierarchically mesoporous titanosilicate Ti-SBA-1

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Chinese Chemical Letters 2015年第10期26卷 1269-1272页

作者： Na Li Rui Chen Jing Miao Peng Zhou Hai-Bin Yu Tie-Hong Chen Institute of New Catalytic Materials science Key Laboratory of Advanced Energy Materials Chemistry(MOE) College of ChemistrySchool of Materials Science and Engineering Nankai University College of Metallurgy Engineering Hunan University of Technology CNOOC Tianjin Chemical Research & Design Institute

Hierarchically mesoporous titanosilicate Ti-SBA-1 was synthesized with organic mesomorphous complexes of polyelectrolyte（poly（acrylic acid）（PAA）） and cationic surfactant（hexadecyl pyridinium chloride（CPC）） as template, tetraethylsiloxane as silica source and titanium ethoxide as titanium source.By adjusting the amount of titanium ethoxide in the synthesis, a series of Ti-SBA-1 particles with different Si/Ti ratio（79–180） were prepared. After incorporation of Ti into the silica framework the wellordered cubic Pm3n mesostructure remained, as well as the morphology, particle size. UV–vis DR spectra of the Ti-SBA-1 materials indicated that incorporated titanium species existed in a highly dispersed state and exhibited tetrahedral and octahedral coordination in the silica framework.

关键词： Ti-SBA-1 Hierarchical Mesoporous Titanosilicate

Effects of phenolic acids on soil nitrogen mineralization over successive rotations in Chinese fir plantations

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Journal of Forestry Research 2020年第1期31卷 303-311页

作者： Long-Chi Chen Xin Guan Qing-Kui Wang Qing-Peng Yang Wei-Dong Zhang Si-Long Wang Huitong Experimental Station of Forest Ecology Institute of Applied EcologyChinese Academy of SciencesShenyang 110016People’s Republic of China hunan Key Laboratory for Structure and Ecosystem Service of Subtropical Forest Huitong National Research Station of Forest EcosystemHuitong 418307People’s Republic of China

Phenolic acids are secondary metabolites of plants that significantly affect nutrient cycling processes.To investigate such effects,the soil available nitrogen(N)content,phenolic acid content,and net N mineralization rate in three successive rotations of Chinese fir plantations in subtropical China were *** N mineralization and nitrification rates in soils treated with phenolic acids were measured in an ex situ experiment.Compared with first-rotation plantations(FCP),the contents of total soil nitrogen and nitrate in second(SCP)-and third-rotation plantations(TCP)decreased,and that of soil ammonium increased.Soil net N mineralization rates in the second-and third-rotation plantations also increased by 17.8%and 39.9%,respectively.In contrast,soil net nitrification rates decreased by 18.0%and 25.0%,respectively.The concentrations of total phenolic acids in the FCP soils(123.22±6.02 nmol g^-1)were 3.0%and 17.9%higher than in the SCP(119.68±11.69 nmol g^-1)and TCP(104.51±8.57 nmol g^-1,respectively).The total content of phenolic acids was significantly correlated with the rates of net soil N mineralization and net nitrification.The ex situ experiment showed that the net N mineralization rates in soils treated with high(HCPA,0.07 mg N kg^-1 day^-1)and low(LCPA,0.18 mg N kg^-1 day^-1)concentrations of phenolic acids significantly decreased by 78.6%and 42.6%,respectively,comparing with that in control(0.32 mg N kg^-1 day^-1).Soil net nitrification rates under HCPA and LCPA were significantly higher than that of the control.The results suggested that low contents of phenolic acids in soil over successive rotations increased soil net N mineralization rates and decreased net nitrification rates,leading to consequent reductions in the nitrate content and enhancement of the ammonium content,then resulting in enhancing the conservation of soil N of successive rotations in Chinese fir plantation.

关键词： Secondary metabolics Nitrogen cycle Chinese fir Vanillin Vanillic acid q-Hydroxybenzoicacid

Extraction and identification of membrane proteins from black widow spider eggs

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Zoological Research 2015年第4期36卷 248-254页

作者： Si-Ling FU Jiang-Lin LI Jia CHEN Qiu-Ting WANG Jian-Jun LI Xian-Chun WANG Key Laboratory of Protein Chemistry and Developmental Biology of Ministry of Education of China Hunan Normal University Molecular sciences and Biomedicine Laboratory State Key Laboratory for Chemo/Biosensing and Chemometrics College of Biology Collaborative Innovation Center for Chemistry and Molecular Medicine Hunan University

The eggs of oviparous animals are storehouses of maternal proteins required for embryonic development. Identification and molecular characterization of such proteins will provide much insight into the regulation of embryonic development. We previously analyzed soluble proteins in the eggs of the black widow spider （Latrodectus tredecimguttatus）, and report here on the extraction and mass spectrometric identification of the egg membrane proteins. Comparison of different lysis solutions indicated that the highest extraction of the membrane proteins was achieved with 3%-4% sodium laurate in 40 mmol/L Tris-HCI buffer containing 4% CHAPS and 2% DTT （pH 7.4）. SDS-PAGE combined with nLC- MS/MS identified 39 proteins with membranelocalization annotation, including those with structural, catalytic, and regulatory activities. Nearly half of the identified membrane proteins were metabolic enzymes involved in various cellular processes, particularly energy metabolism and biosynthesis, suggesting that relevant metabolic processes were active during the embryonic development of the eggs. Several identified cell membrane proteins were involved in the special structure formation and function of the egg cell membranes. The present proteomic analysis of the egg membrane proteins provides new insight into the molecular mechanisms of spider embryonic development.

关键词： Latrodectus tredecimguttatus Egg Membrane protein Extraction Identification

Effects of pre-moxibustion at Zusanli (ST36) on heat shock protein 70 expression in rats with gastric mucosal lesions after neurotomy

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Neural Regeneration Research 2012年第30期7卷 2370-2376页

作者： Liang Peng Mi Liu Xiaorong Chang Zhou Yang Shouxiang Yi Jie Yan Yan Peng College of Acupuncture and Tuina Hunan University of Chinese Medicine Changsha 410007 Hunan Province China

Studies have shown that pre-moxibustion protects the gastric mucosa by up-regulating the expression of heat shock protein 70. However, the signaling pathway underlying this effect remains unclear. Rats were intragastrically administered absolute alcohol, causing obvious lesion of the gastric mucosa. Following pre-moxibustion at Zusanfi （ST36） for 8 days, the ulcer index decreased to different degrees. The results of an enzyme linked immunosorbent assay and western blotting showed significant upregulation of heat shock protein 70 expression in the gastric mucosa and serum. None out of transection of the spinal cord, damage to the nucleus of the solitary tract, neurotomy of the vagal nerve and neurotomy of the common peroneal nerve affected the decrease in ulcer index or the increase in heat shock protein 70 expression in serum after pre-moxibustion at Zusanfi, and heat shock protein 70 expression was obviously decreased in the gastric mucosa. These findings suggest that pre-moxibustion at Zusanfi can protect the gastric mucosa against lesioning, and that the mechanism underlying this effect involves its induction of heat shock protein 70 expression. Neural pathways participate in the regulatory effects of moxibustion on heat shock protein 70 expression in the gastric mucosa.

关键词： pre-moxibustion transection of neural pathway Zusanli （ST36） gastric mucosal lesion heat shockproteins-70 ulcer index traditional Chinese medicine neural regeneration

丙丁酚抑制体外氧化低密度脂蛋白诱导的单核细胞对内皮细胞的粘附(英文)

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Acta Pharmacologica Sinica 2002年第6期23卷 38-44页

作者：刘革修欧大明李立新陈临溪黄红林廖端芳唐朝枢中国 100034 北京大学第一医院心血管研究所衡阳 421001 南华大学药物药理研究所

目的:研究丙丁酚抑制体外氧化低密度脂蛋白诱导的单核细胞对内皮细胞的粘附机制.方法:采用酶联免疫法检测丙丁酚对内皮细胞粘附分子、细胞间粘附分子1(ICAM-1)、血管细胞粘附分子1 (VCAM-1)、P-选择素和E-选择素表达的影响,对比分析丙... 详细信息

目的:研究丙丁酚抑制体外氧化低密度脂蛋白诱导的单核细胞对内皮细胞的粘附机制.方法:采用酶联免疫法检测丙丁酚对内皮细胞粘附分子、细胞间粘附分子1(ICAM-1)、血管细胞粘附分子1 (VCAM-1)、P-选择素和E-选择素表达的影响,对比分析丙丁酚和上述粘附分子单克隆抗体抑制氧化低密度脂蛋白诱导的单核细胞对内皮细胞的粘附作用.结果:丙丁酚呈浓度依赖性抑制氧化低密度脂蛋白诱导的单核细胞对内皮细胞的粘附,丙丁酚浓度从10μmol/L增加到80μmol/L,单核细胞对内皮细胞的粘附从16.7％降低至7.0％(P<0.01),同时ICAM-1和P-选择素表达分别被抑制75％和72％(P

关键词：丙丁酚 LDL脂蛋白类粘附血管内皮培养的细胞单核细胞 P-选择素 E-选择素细胞间粘附分子-1 血管细胞粘附分子-1

A Novel Method for Modification of SMPU by Micro-phase

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Chinese Chemical Letters 2005年第9期16卷 1241-1244页

作者： Shao Jun CHEN Jing Cang SU Peng Sheng LIU Research Institute of Polymeric Materials Xiangtan University Xiangtan 411105

A novel method of controlling the shape memory properties of shape memory polyurethane （SMPU） by addition of micro-phase separation promoters including 1-octadecanol （ODO） and liquid paraffin （LP） is reported. The results indicate that the strain recovery temperature and the strain modulus rate （Eg/Er） were increased significantly with addition of small amount of micro-phase separation promoters. Thus it can increase the shape memory fixity rate and other shape memory behaviors of SMPU.

关键词： Shape memory polyurethane modification micro-phase separation

17β-雌二醇对去卵巢胰岛素抵抗大鼠主动脉舒缩功能损伤的保护作用

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生理学报 2005年第5期57卷 627-635页

作者：周寿红凌宏艳田绍文刘显庆王炳香胡弼南华大学医学院生理学教研室衡阳421001

为观察17β-雌二醇(17beta-estradiol,17β-E2)对去卵巢胰岛素抵抗(insulin resistance,IR)大鼠主动脉结构和舒缩功能的影响及其可能机制,成年雌性Sprague-Dawley大鼠卵巢切除后,高果糖喂养8周诱导IR,同时给予生理剂量的17β-E2(30 μg... 详细信息

为观察17β-雌二醇(17beta-estradiol,17β-E2)对去卵巢胰岛素抵抗(insulin resistance,IR)大鼠主动脉结构和舒缩功能的影响及其可能机制,成年雌性Sprague-Dawley大鼠卵巢切除后,高果糖喂养8周诱导IR,同时给予生理剂量的17β-E2(30 μg／kg),每天皮下注射一次,并检测IR相关指标。大鼠胸主动脉石蜡切片,HE染色,图像分析系统测定其结构。采用血管环灌流法,观察各组大鼠胸主动脉环对新福林(L-phenylephrine,PE)的收缩反应和对ACh、硝普钠(sodium nitroprusside, SNP)的舒张反应以及一氧化氮合酶(nitric oxide synthase,NOS)抑制剂N-硝基-L-精氨酸甲脂(N-nitrl-L-arginine methyl ester,L- NAME)对卵巢切除+果糖喂养+17β-E2组大鼠胸主动脉Ach的舒张反应的影响;检测各组大鼠一氧化氮(nitric oxide,NO) 含量。结果显示:(1)17β-E2能防止高果糖诱导的去卵巢IR大鼠收缩压升高、高胰岛素血症和胰岛素敏感性下降:(2)各组大鼠胸丰动脉的结构无显著性差异;(3)卵巢切除+果糖喂养组大鼠与卵巢切除组或果糖喂养组相比,血清NO显著降低, 胸主动脉对PE的收缩反应显著增强,对ACh的舒张反应显著降低,17β-E2能逆转上述改变,L-NAME可部分阻断17β-E2 的这种作用;(4)各组大鼠胸主动脉对SNP的舒张反应和去内皮后对PE的收缩反应均无显著差异。以上结果表明,17β-E2能抑制高果糖诱导的去卵巢IP大鼠血管舒缩功能的紊乱,其机制一方向可能是部分通过血管内皮细胞NOS途径促进N0的释放, 保护内皮细胞;另一方面可能是通过降低血压,血清胰岛素水平,改善IR所致。

关键词：雌二醇果糖去卵巢胰岛素抵抗主动脉内皮细胞