992 resultados para saline hypertonique


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本文综述了放线菌分类学研究的目的和作用,分析了放线菌分类学的历史和现状,介绍了当前放线菌多相分类研究中所采用的技术方法及适用范围。同时还重点介绍了极端高温、低温、高盐放线菌分离及分类研究的进展。从云南采集高温温泉水样、火山口土样,从云南、新疆等地采集雪山土样,从新疆、青海等地采集盐碱土样进行放线菌分离,对不同极端环境下的放线菌分离方法进行探讨,并对分离到的部分典型放线菌菌株采用形态特征、培养特征,生理生化测定,细胞化学组份分析,DNA G+C mol%和DNA同源性测定,以及16SrDNA全序列分析等相结合的多相分类技术进行系统的分类研究。从表型、基因型及系统发育三个不同层次对其分类地位进行了最终确定。其中,分离自云南洱源温泉的菌株YIM60013和腾冲火山口的菌株YIM60032分别确定为高温放线菌属的两个新种:白色高温放线菌(Thermoactznomyces albus sp. nov.)和云南高温放线菌(Termoactomyces yunnanensis sp. nov.);分离自新疆北疆地区的一株低温放线菌菌株,结合其形态特征、细胞化学组份及16S rDNA序列分析将其鉴定为链霉菌的一个新种,北疆链霉菌(Streptomyces beijiangensis sp. nov.);来自新疆盐碱土样的6株嗜盐放线菌菌株YIM90001-90006中,菌株YIM90001被命名为嗜盐普氏菌新种(Prauserella halophila sp. nov.),菌株YIM90005被 命名为脱卤普氏菌新种(Prauserella dehalogenans sp. nov.),菌株YIM90002和YIM90003鉴定为拟诺卡氏菌科中的链单抱菌新属Streptomonospora gen. nov.)和它的两个新种:菌株YIM90002定为盐生链单抱菌新种(Streptomonospora saline sp. nov.),菌株YIM90003定为白色链单抱菌新种(Streptomonospora alba sp. nov.);菌株YIM90004和YIM90006分别被确定为拟诺卡氏菌属的一个新种和一个亚种:新疆拟诺卡氏菌新种(Nocardopsi sxiniangensis sp. nov.)和嗜阿拉伯糖新疆拟诺卡氏菌亚种( Noocardiopsi sxiniangensis subsp.arabicus subsp.nov,)。

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本文通过微区、盆裁和根际试验相结合的方法,研究了有机物料对黄河三角洲东营滨海盐土的盐分、养分动态和酶活性的影响,结果表明,盆裁和微区试验土壤盐分随稻草粉用量增大而递增,主要在于二价离子的上升;土壤交换性钙、镁、钾上升,钠下降;土壤pH略有降低,土壤速效氮、磷、钾养分明显上升。有机物料对土壤铁、锌活化作用明确,而对锰、铜影响不大。有机物料能增强土壤转化酶、碱性磷酸酶和脲酶的活性,从而对提高土壤有机质矿化的速率,以及改善作物的根际养分状况具有良好作用。

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Salt water intrusion occurred frequently during dry season in Modaomen waterway of the Pearl River Estuary. With the development of region's economy and urbanization, the salt tides affect the region's water supply more and more seriously in recent years. Regulation and allocation of freshwater resources of the upper rivers of the estuary to suppress the salt tides is becoming important measures for ensuring the water supply security of the region in dry season. The observation data analysis showed that the flow value at the Wuzhou hydrometric station on the upper Xijiang river had a good correlation with the salinity in Modaomen estuary. Thus the flow rate of Wuzhou has been used as a control variable for suppression of salt tides in Modaomen estuary. However, the runoff at Wuzhou mainly comes from the discharge of Longtan reservoir on the upper reaches of Xijiang river and the runoff in the interval open valley between Longtan and Wuzhou sections. As the long distance and many tributaries as well as the large non-controlled watershed between this two sections, the reservoir water scheduling has a need for reasonable considering of interaction between the reservoir regulating discharge and the runoff process of the interval open watershed while the deployment of suppression flow at Wuzhou requires longer lasting time and high precision for the salt tide cycles. For this purpose, this study established a runoff model for Longtan - Wuzhou interval drainage area and by model calculations and observation data analysis, helped to understand the response patterns of the flow rate at Wuzhou to the water discharge of Longtan under the interval water basin runoff participating conditions. On this basis, further discussions were taken on prediction methods of Longtan reservoir discharge scheduling scheme for saline intrusion suppression and provided scientific and typical implementation programs for effective suppression flow process at the Wuzhou section.

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人类的载脂蛋白A5(apolipoprotein A5,APOA5)是一个新近发现的载脂蛋白家族成员。它在血浆中的含量比其他载脂蛋白低1-2个数量级,但能显著影响血浆三酰甘油水平,对血脂代谢具有重要意义,可以作为降血脂药物治疗中一个强有力的潜在靶标。 由于APOA5在血浆中含量低,直接从血浆中分离纯化很困难,国内一直没有报道简易可靠的纯化方法。为进一步研究APOA5的生物学特性,探讨其与TG代谢中的其它关键成分之间的相互关系,揭示其在脂类代谢相关疾病中的重要地位,必须有大量的蛋白和抗体用于基础研究。因此本研究首先利用基因工程技术,诱导表达纯化APOA5蛋白,免疫动物制备多克隆抗体,为进一步研究人肝脏细胞中APOA5的相互作用蛋白,研究APOA5蛋白在肝脏细胞中的功能奠定基础。 为了深入研究APOA5在肝脏中如何行使功能,我们采用细菌双杂交技术寻找与APOA5相互作用的蛋白因子。并采用Pull-down技术,免疫荧光及免疫共沉淀技术进一步确证其在体外和体内的相互作用关系,为进一步阐明APOA5在体内的生理功能提供了新的线索。 第一部分 APOA5基因的克隆、原核表达、纯化及其多克隆抗体的制备 本研究首先应用基因克隆技术,从人肝癌细胞系SMMC-7721的cDNA中扩增出1.1 kb的ApoA5基因全长序列。然后将其克隆至表达载体pThioHisD,构建原核表达载体pTH-APOA5。该重组质粒转化至大肠杆菌 BL21(DE3),成功实现人APOA5融合蛋白在大肠杆菌中的表达。经发酵得到高效表达的融合蛋白。 融合蛋白在 IPGT 诱导下以包涵体的形式大量表达。利用融合蛋白上的一段组氨酸序列,用镍离子亲和柱进行纯化和复性后,获得较高纯度的人APOA5融合蛋白。利用该融合蛋白免疫新西兰大耳白兔,获得了高效价的兔抗人APOA5多克隆抗体,Western Blot结果显示此多克隆抗体与APOA5特异性结合。 第二部分 细菌双杂交筛选与APOA5相互作用的蛋白 本实验首先构建了pBT-APOA5重组质粒,经双酶切、PCR和测序鉴定证明重组诱饵质粒构建成功,并进行了表达、自激活鉴定。Western Blot鉴定证实报告菌株中表达了分子量为 68 kD左右的重组融合蛋白,与预测的分子量APOA5(41 kD)/lamda cI (27 kD)一致。自激活实验证明诱饵蛋白不能单独激活报告基因,可用于筛选人肝脏cDNA文库。经过双重抗性筛选和回复筛选,分离出10个阳性克隆。对结果进行生物信息学分析,得到7个与APOA5相互作用的蛋白,其中BI1为细胞凋亡调节因子;ATP6、CYTB、ND2、COX-1为线粒体表达蛋白; ALB、TTR为血清蛋白。 第三部分 APOA5与BI1相互作用的确证 首先构建了BI1的原核表达载体pGEX-5X-3-BI1,利用Pull-down实验检测了APOA5与BI1在体外具有相互作用。然后构建了BI1的真核表达载体pCDNA3.1-HA-BI1和APOA5的真核表达载体pCDNA3.1-APOA5,并验证其表达。通过免疫荧光细胞内共定位研究发现,靶蛋白APOA5主要分布于胞浆,与BI1在HEK293细胞有共定位,即APOA5与BI1存在相互作用的可能。最后利用免疫共沉淀手段,在HEK293细胞中确证了靶蛋白APOA5与BI1在体内的相互作用。 上述研究结果,为深入研究APOA5在体内的生物学功能提供了新的思路。 Apolipoprotein A5 (APOA5) is a newly discovered protein belongs to apolipoprotein family. APOA5’s concentration is 1-2 orders of magnitude lower than other apolipoproteins in the circulation. APOA5 significantly affected plasma triglyceride levels, which is important on lipid metabolism. APOA5 has strong potential to be used as a hypolipidemic drug target. Large amount of APOA5 protein and antibodies are needed in basic research, such as biological characteristics study of the APOA5, its relationship with other key components in TG metabolism, its role played in Lipid metabolism-related diseases. Due to its low concentration in plasma, separation and purification of APOA5 from the plasma is very difficult. Until now no report on simple and reliable method for purification has been published in China. In this study, we firstly got APOA5 recombinant protein using genetic engineering technology. The purified recombinant protein was used to immunize rabbits to get antiserum. It is important for further study of the APOA5 protein-interacting protein. And it lays the foundation for studing APOA5 function in liver. In order to study APOA5 function in liver, we used bacterial two-hybrid technology to find the APOA5 protein interactor. Pull-down, immunofluorescence and immunoprecipitation techniques were used to further confirm the interaction between APOA5 with its interactor in vitro and in vivo. All of these stdudies provided new clues on its physiological functions in vivo. Part I: Cloning, prokaryotic expression, purification and polyclonal antibody preparation of APOA5 First of all, we amplified APOA5 CDS sequence from the human hepatoma cell line SMMC-7721, and subcloned into Expression vector pThioHisD, and got the recombinants named pTH-APOA5. The plasmid was transformed to BL21 (DE3). E. coli BL21(DE3) cells bearing the pTH-APOA5 plasmid were cultured and APOA5 protein synthesis was induced by the addition of IPTG. Recombinant protein was expression in the form of inclusion. Inclusion bodies were dissolved in phosphate-buffered saline containing 8 M urea and 40 mM imidazole, then applied to a Ni2+ affinity column, and were eluted in a buffer containing 4 M urea and 200 mM imidazole. Fractions containing the APOA5 protein were pooled and dialyzed against buffer containing phosphate-buffered saline. Antiserum to recombinant human APOA5 was generated by immuning rabbit. Western Blot showed that this antiserum specific binding with APOA5. Part II Two-hybrid system screening protein interactions with the APOA5 The coding sequence of human APOA5 was amplified using synthetic oligonucleotide primers from pTH-APOA5 vector and was subcloned into the pBT plasmidc to yield pBT-APOA5 vector. DNA sequencing was performed to verify that no unwanted mutations occurred during the process of plasmid vector construction. We verified recombinant protein expression and tested self-activation by pBT-APOA5 prior to screening. Western Blot verified inducing a 68 kD band, consistent with the predicted molecular weight (APOA5 41 kD, lamda cI 27 kD). pBT-APOA5 can be used for screening human liver cDNA library because it can not self-activation. Totally 10 positive clones were isolated. The nucleotide sequence of the positive clones were determined and compared to NCBI nucleotide sequence databases. We got 7 protein which interact with APOA5, included BI1(Apoptosis regulator); ATP6, CYTB, ND2, COX-1(Mitochondrial protein) and ALB, TTR(Serum protein). Part III Confirming of interaction between APOA5 with BI1 pGEX-5X-3-BI1 vector was subcloned at first. Pull-down experiments were used to detect the interaction between APOA5 with BI1 in vitro. Later, pCDNA3.1-HA-BI1 and pCDNA3.1-APOA5 were subcloned. Through immunofluorescence co-localization study, we found APOA5 mainly distributed in the cytoplasm. APOA5 is co-localization with BI1 in HEK293 cells. Finally, we verified interaction between APOA5 with BI1 in vivo through immunoprecipitation.

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BACKGROUND: Hypoxia and ischemia induce neuronal damage, decreased neuronal numbers and synaptophysin levels, and deficits in learning and memory functions. Previous studies have shown that lycium barbarum polysaccharide, the most effective component of barbary wolfberry fruit, has protective effects on neural cells in hypoxia-ischemia. OBJECTIVE: To investigate the effects of Naotan Pill on glutamate-treated neural cells and on cognitive function in juvenile rats following hypoxia-ischemia. DESIGN, TIME AND SETTING: The randomized, controlled, in vivo study was performed at the Cell Laboratory of Lanzhou University, Lanzhou Institute of Modern Physics of Chinese Academy of Sciences, and Department of Traditional Chinese Medicine of Gansu Provincial Rehabilitation Center Hospital, China from December 2005 to August 2006. The cellular neurobiology, in vitro experiment was conducted at the Institute of Human Anatomy, Histology, Embryology and Neuroscience, School of Basic Medical Sciences, Lanzhou University, and Department of Traditional Chinese Medicine of Gansu Provincial Rehabilitation Center Hospital, China from March 2007 to January 2008. MATERIALS: Naotan Pill, composed of barbary wolfberry fruit, danshen root, grassleaf sweetflag rhizome, and glossy privet fruit, was prepared by Gansu Provincial Rehabilitation Center, China. Rabbit anti-synaptophysin, choline acetyl transferase polyclonal antibody, streptavidin-biotin complex kit and diaminobenzidine kit (Boster, Wuhan, China), as well as glutamate (Hualian, Shanghai, China) were used in this study. METHODS: Cortical neural cells were isolated from neonatal Wistar rats. Neural cell damage models were induced using glutamate, and administered Naotan Pill prior to and following damage. A total of 54 juvenile Wistar rats were equally and randomly assigned into model, Naotan Pill, and sham operation groups. The left common carotid artery was ligated, and then rat models of hypoxic-ischemic injury were assigned to the model and Naotan Pill groups. At 2 days following model induction, rats in the Naotan Pill group were administered Naotan Pill suspension for 21 days. In the model and sham operation groups, rats received an equal volume of saline. MAIN OUTCOME MEASURES: Neural cell morphology was observed using an inverted phase contrast microscope. Survival rate of neural cells was measured by MTT assay. Synaptophysin and choline acetyl transferase expression was observed in the hippocampal CA1 region of juvenile rats using immunohistochemistry. Cognitive function was tested by the Morris water maze. RESULTS: Pathological changes were detected in glutamate-treated neural cells. Neural cell morphology remained normal after Naotan Pill intervention. Absorbance and survival rate of neural cells were significantly greater following Naotan Pill intervention, compared to glutamate-treated neural cells (P < 0.05). Synaptophysin and choline acetyl transferase expression was lowest in the hippocampal CA1 region in the model group and highest in the sham operation group. Significant differences among groups were observed (P < 0.05). Escape latency and swimming distance were significantly longer in the model group compared to the Naotan Pill group (P < 0.05). CONCLUSION: Naotan Pill exhibited protective and repair effects on glutamate-treated neural cells. Naotan Pill upregulated synaptophysin and choline acetyl transferase expression in the hippocampus and improved cognitive function in rats following hypoxia-ischemia.

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该文在对新疆水土流失的现状、特点的分析的基础上 ,对现实存在着的水蚀强度、戈壁的风蚀强度、盐碱地的归属和侵蚀交错类型的分隔等问题进行了讨论 ,提出了自己的观点和看法 ,为水土流失调查提供借鉴

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A variety of the perennial herbage in knotweed which was recently introduced to China has characteristics of high fresh yield, rich nutrient matter and wide adaptability, and many way of development and application. In addition , the hybrid Rumex has great ability for cold resistance, drought enduring, and resistance to saline alkali and poor soil. But, this herbage is very sensitive to water, fertilizer and temperature. High yield and fine quality of the herbage are of the basis of the material rewards. The observation is necessary for the safe live of this herbage through the winter at high latitudes and special year

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天津东郊盐碱土微生物分布及土壤酶活性靳素英,崔明学,蔺继尚(中国科学院沈阳应用生态研究所,沈阳110015)Distributionofmicroorganismsinsaline-alkalisoilatcasternsuburbsofTianji...

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The conformation of bovine serum albumin (BSA), as well as its interactions with negatively charged mica surfaces in saline solutions of different pH values, have been studied by small-angle neutron scattering (SANS) and chemical force microscopy (CFM), respectively. A new approach to extract the contribution of elementary interactions from the statistically averaged force-extension curves through self-consistent fitting was proposed and used to understand the effects of pH on the interactions and conformation of BSA in saline solutions. When pH increases, the SANS results reveal that the sizes of BSA molecules increase slightly, while the statistical analysis of the CFM results shows that the averaged pull-off force for the elongation monotonously decreases. The decrease of pull-off force with the increase of pH results from the decrease in the strength of hydrogen bonding and the number of interaction pairs, as well as the slight increase of the strength of van der Waals interaction. When pH approaches the isoelectric point (pI) of BSA, results from both SANS and CFM suggest a loss of long-range interactions in BSA molecules. Our results also suggest that the force-extension curve is mainly contributed by the van der Waals interaction. The combination of SANS and CFM provides new insight to understand the interactions and conformation of BSA molecules

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The responses of stem segments of watercress (Nasturtium officinale R. Br.) to 6-BA,NAA and 2,4-D were studied. MS medium supplemented with 2.0 mg/L 6-BA, 0.2 mg/L 2,4-D was used for callus initiation and maintenance. MS medium supplemented with 4.0 mg/L 6-BA was suitable for plant regeneration and MS medium without plant hormone supplement was used for rooting and plant propagation. For screening of salt tolerant calli, stem segments of watercress were plated onto callus initiation medium containing 1/3 natural seawater. Seventeen out of the 325 plated explants produced calli. The growth curves demonstrated that the growth rate of salt-tolerant calli on saline medium almost matched that of the control calli on normal medium. Some of the salt-tolerant calli were transferred to the normal regeneration medium or saline regeneration medium to induce plant regeneration. In the first case, buds and shoots were regenerated in the same way as those of control calli on normal regeneration medium. More than 1 000 regenerated shoots were obtained of which 83 regenerated shoots were cut and transferred to saline MS base medium. At first, all shoot growth was inhibited, but 40 days after the transfer, rapid-growing axillary shoots were observed on 16 of the original shoots but none on the control shoots on saline MS base medium. Moreover, green spots appeared on most calli 10 days after they were transferred to saline medium, however buds appeared only on 5 calli from the 30 transferred calli and at the end only 2 rapid-growing shoots were obtained from two calli. In total, 18 variant lines were obtained through. propagation of the salt-tolerant shoots on saline MS base medium. RAPD analysis was performed in 10 of the 18 salt-tolerant variant lines and DNA variation was detected in all the tested variant lines.

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We collected fish abundance data in the Changjiang (Yangtze River) estuary and adjacent waters in November 1998, May 1999, November 2000, and May 2001. Using the data, we evaluated the characteristics of the fish assemblages at each site and investigated the effect of several environmental factors. We used a multivariate analysis, including community ordination methods such as detrended correspondence analysis (DCA) and canonical correspondence analysis (CCA), and two-way indicator species analysis (TWINSPAN). We analyzed the biological community structure and environmental factors to determine their spatial distributions, temporal dynamics, and seasonal variations. Among the fish species, five exceeded 5% of the total abundance: Harpodon nehereus (42.82%), Benthosema pterotum (13.85%), Setipinna taty (11.64%), Thryssa kammalensis (9.17%) and Apogonichthys lineatus (6.49%). These were separated into four ecological assemblages: hypsithermal-saline, hypsithermal-brackish, hypothermal-brackish, and hypothermal-saline. We evaluated the degree of influence of environmental factors on the fish community. Our analyses suggested that environmental factors including water depth, salinity, turbidity, transparency, nutrient, and suspended matter formed a synthetic spatial gradient between the coastal and pelagic areas. Ecological and environmental factors changed temporally from 1998 to 2001, and drove the fish community succession. The environmental factors driving the fish community structure included bottom temperature, water depth, bottom and surface pH, surface total phosphorous, and bottom dissolved oxygen. This investigation was completed before completion of the Three Gorges Dam; therefore the results of this study provide an important foundation for evaluating the influence of the human activities.

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Growth hormone (GH) effectively promotes seawater (SW) adaptation in salmonids, but little is known of its effect in tilapias. Experiments were performed to investigate the effects of recombinant eel GH (reGH) on osmoregulatory actions and ultrastructural features of gill chloride cells in juvenile tilapia, Oreochromis niloticus. Tilapia showed a markedly improved SW survival, when directly transferred from freshwater (FW) to 62.5% SW 24h after a single reGH injection (0.25 or 2.5 mu g g(-1)) or 3 reGH injections (0.25 mu g g(-1) every other day). Plasma Na+ and Mg2+ levels were significantly reduced by reGH (0.25 and 2.5 mu g g(-1)) compared with saline injections; Ca2+ concentrations were reduced significantly by high dose of reGH (2.5 mu g g(-1)) after SW transfer. However, fish failed to survive more than 24h when directly transferred to 70 % SW, although the fish treated with reGH could survive longer than the controls. When examined by electron microscopy, the chloride cells were identified as mitochondrion-rich and an extensive tubular system was induced by GH treatment. The results of the present study suggest that, similar to its effect on salmonids, GH also exerts acute osmoregulatory actions and enhances SW adaptation in juvenile tilapia. GH also stimulates the differentiation of chloride cells toward SW adaptation.

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The impact of transient wind events on an established zooplankton community was observed during a, field survey in a, coastal region off northern Norway in May 2002. A transient wind event induced a coastal jet/filament intrusion of warm, saline water into our survey area where a semi-permanent eddy was present. There was an abrupt change in zooplankton community structure within 4-7 days of the wind event, with a change in the size structure, an increase in lower size classes less than 1 mm in equivalent spherical diameter (ESD) and a decrease in larger size classes greater than 1.5 mm in ESD. The slope of zooplankton biovolume spectra changed from -0.6 to -0.8, consistent with the size shifting towards smaller size classes. This study shows that even well established zooplankton communities are susceptible to restructuring during transient wind events, and in particular when wind forcing induces horizontal currents or filaments.

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Copepod species diversity, abundance and assemblages in relation to water masses over the continental shelf of the Yellow Sea (YS) and East China Sea (ECS) were studied extensively based on the net plankton samples in autumn 2000. Multivariate analysis based on copepod assemblage resulted in recognition of five groups (Groups 1-5) corresponding to the water masses. Groups 1 and 2 delineated from inshore stations with low salinity YS Surface Water, and offshore stations with YS Cold Water in the YS. Group 3 located in the joint area of YS and ECS mainly with Mixed Water. Groups 4 and 5 in the ECS delineated two assemblages mainly from inshore and shallow stations with ECS Mixed Water in the southeastern ECS, and offshore stations along the ECS shelf edge controlled by saline Kuroshio Water. Salinity and temperature were more important in characterizing copepod assemblage of the continental shelf than chlorophyll a. (c) 2005 Elsevier B.V. All rights reserved.

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MP-25 resin is a chlorine-containing polymer widely used in coatings. The effects of two types of nano-TiO2 (P-25 and RM301 LP) on MP-25 were studied with saline immersion, UV irradiation, and electrochemical impedance spectroscopy. UV irradiation was evaluated in terms of gloss change and X-ray photoelectron spectroscopy (XPS). The results indicate that, compared to pigment R-930 TiO2, P-25 reduced the immersion resistance and accelerated UV aging of the MP-25 coating, whereas RM301 LP showed the opposite effects. XPS analysis showed that MP-25 resin degraded under UV irradiation via dechlorination and C-C bond breakage, similarly to poly(vinyl chloride), but RM301 LP could inhibit the aging of MP-25 to a certain extent. A skin effect of oxygen and chlorine was identified in MP-25 resin by XPS. RM301 LP could improve the impedance of the MP-25 coating because of its excellent fill capacity. Hence, rutile nano-TiO2 RM301 LP represents an excellent additive for MP-25 resin. (c) 2007 Wiley Periodicals, Inc.