钛基钌系氧化物涂层阳极电催化水处理活性与失活

电催化氧化是一种环境友好型水处理技术。钛基钌系氧化物涂层阳极在电催化水处理中的活性与失活对其使用效率和寿命至关重要。钛基钌系氧化物涂层阳极电催化活性主要来源于氧化物原子桥位产生的活性位及表面电子态,活性机理可归为价态转变、晶格氧输运及原位吸附活性位的产生。阳极失活主要是涂层溶蚀、TiO2钝化膜生成和涂层“毒化”等原因造成。通过增加中间层、掺杂、构建梯度型涂层及消除p-n结等途径可抑制阳极失活,提高使用寿命。

天然炭纤维负载二氧化钛颗粒的制备与光催化活性

以棉花制备的炭纤维为载体,钛酸丁酯为钛源,采用水热法制备炭纤维负载二氧化钛复合材料(CF/Ti O2),利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)等对CF/Ti O2复合材料进行结构表征。用紫外-可见光吸收光谱(UV-vis)分析比较了Ti O2、炭纤维和CF/Ti O2,热处理温度以及溶液的p H值在紫外光照下对甲基蓝溶液的光催化降解性的影响,以及对CF/Ti O2复合材料的失活性能研究。结果表明:炭纤维负载Ti O2对甲基蓝光催化降解性较好,有效利用了炭纤维的吸附性与Ti O2的催化活性;当热处理温度为220℃,p H=5时,甲基蓝溶液的吸附-光催化性能最大为85.9%;复合光催化剂使用后在紫外线照射后,其活性恢复,可以循环利用。

汽油吸附用煤基活性炭的制备及研究

为降低汽油吸附用活性炭的生产成本,拓展其原料来源,以大同煤和山东煤为原料,考察了配煤比、炭化及活化工艺参数对汽油吸附用活性炭性能的影响,探究了活性炭孔结构对正丁烷工作容量的影响。结果表明,大同煤与山东煤质量比为9:1时,适宜于制备汽油吸附用活性炭;活性炭烧失率的增加,有利于提高其吸附性能,当烧失率为80%~85%时,其正丁烷工作容量达到11.5 g/100 m L。2 nm^4 nm中孔活性炭有利于对汽油蒸汽的吸附;炭化温度在550℃~650℃范围内,对活性炭性能几乎不影响。

G蛋白偶联受体突变及其相关疾病

G蛋白偶联受体(GPCR)是最大的蛋白质受体超家族之一,参与调节各种生理过程,在信号识别和转导中起重要作用。GPCR的突变及基因多态性将引发各种疾病,目前已经发现有30多种单基因疾病与此相关。介绍了GPCR功能失调的分子基础,在此基础上对一些GPCR突变以及相关疾病做了综述,并指出了其治疗意义。

柴油车用钒基催化剂水热老化性能研究

针对钒系SCR催化剂高温水热稳定性差的问题,通过分析老化前后理化性质与催化性能变化,剖析失活本质。与新鲜样品相比,水热老化后,催化剂活性出现不同程度的降低。催化材料的理化表征测试结果表明,催化剂失活很大程度上是由于催化剂涂层中活性元素钒挥发,导致低温催化活性严重衰减。550℃水热老化后的催化剂样品,NO_(x)起燃温度由199℃升高至220℃。同时,催化剂氨存储量(200℃时)由新鲜态的409.52 mg/L降至137.08 mg/L(550℃水热老化后)。说明较高的排气温度与水汽可能会导致催化剂涂层氨吸附能力衰减,削弱其催化反应的本征活性。此外,水热老化后,材料微观表面结构更为致密,比表面积由新鲜态的29.51 m^(2)/g降至11.95 m^(2)/g(550℃水热老化后),导致污染物气体与催化材料的接触面积减小,一定程度降低了催化效率,导致催化活性降低。

Synthesis of Chiral Polyaniline Induced by Modified Hemoglobin

The synthesis of chiral polyaniline （PANI） induced by modified hemoglobin （Hb） was pro- foundly explored for the first time. Results revealed that after being separated, inactivated or immobilized, Hb can still induce the formation of chiral PANI successfully, suggesting that Hb can be used as the chiral inducers regardless of harsh reaction conditions. By examining the properties of PANI induced by modified Hb, it was found that Hb（inactivated）-PANI possessed excellent chirality, stability, and crystalline structure. The globin separated from Hb was demonstrated to have the ability of inducing the production of chiral PANI whereas the hematin from Hb had no capacity to direct enantio specificity for the PANI chains. Results indicated that Hb（immobilized）-PANI exhibited poor yield, doping state, and crys- talline structure, indicating that the immobilization of Hb by entrapment was not beneficial to the polymerization reaction. Results also showed that the structure of Hb may have significant effects on the morphologies of chiral PANI.

The effect of cations(NH_4^+,Na^+,K^+,and Ca^(2+)) on chemical deactivation of commercial SCR catalyst by bromides

Alkali and alkaline‐earth metals from fly ash have a significant deactivation effect on catalysts used for selective catalytic reduction of NOx by NH3(NH3‐SCR).Bromides are considered effective additives to improve Hg0 oxidation on SCR catalysts.In this work,the effects of different bromides(NH4Br,NaBr,KBr,and CaBr2)on a commercial V2O5‐WO3/TiO2 catalyst were studied.NOx conversion decreased significantly over the KBr‐poisoned catalyst(denoted as L‐KBr),while that over NaBr‐and CaBr2‐poisoned catalysts(denoted as L‐NaBr and L‐CaBr,respectivity)decreased to a lesser extent compared with the fresh sample.Poor N2 selectivity was observed over L‐NaBr,L‐KBr and L‐CaBr catalysts.The decrease in the ratio of chemisorbed oxygen to total surface oxygen(Oα/(Oα+Oβ+Ow)),reducibility and surface acidity might contribute to the poor activity and N2 selectivity over L‐KBr catalyst.The increased Oαratio was conducive to the enhanced reducibility of L‐CaBr.Combined with enhanced surface acidity,this might offset the negative effect of the loss of active sites by CaBr2 covering.The overoxidation of NH3 and poor N2 selectivity in NH3 oxidation should retard the SCR activity at high temperatures over L‐CaBr catalyst.The increased basicity might contribute to increased NOx adsorption on L‐KBr and L‐CaBr catalysts.A correlation between the acid‐basic and redox properties of bromide‐poisoned catalysts and their catalytic properties is established.

Inactivation of digestive proteases: Another aspect of gut bacteria that should be taken into more consideration

TO THE EDITOR Protein has been one of the main components of our diet, and a large amount of digestive proteases is released into the gut for their digestion. However, these proteases can digest not only the proteins we eat, but also the structural proteins built in our body. To protect against this damage, our body has taken a variety of measures. For instance, these digestive proteases are stored and secreted in the form of zymogen and only activated in gut lumen. These luminal digestive proteases are further prevented from direct contact with epithelial cells by the mucus layer that is incessantly secreted by the goblet cells in gut mucosa. In addition, large quantities of protease inhibitors are produced in the body to inactivate the digestive proteases that have entered the body. Despite these measures, the protection seems still weak and can be easily compromised. For instance,

NIH 3T3 cells malignantly transformed by mot-2 showinactivation and cytoplasmic sequestration of the p53protein

In previous studies we have reported that a high levelof expression of mot-2 protein results in malignant transformation of NIH 3T3 cells as analyzed by anchorage indeopendent growth and nude mice assays [Kaul et al., Oncogene, 17, 907-11, 1998]. Mot-2 was found to interact withtumor suppressor protein p53. The transient overexpression of mot-2 was inhibitory to transcriptional activationfunction of p53 [Wadhwa et al., J. Biol. Chem., 273, 2958691, 1998]. We demonstrate here that mot-2 transfectedstable clonse of NIH 3T3 that showed malignant propertiesindeed show inactivation of p53 function as assayed byexogenous p53 dependent reporter. The expression levelof p53 in response to UV-irradiation was lower in NIH3T3/mot-2 as compared to NIH 3T3 cells and also exhibited delay in reaching peak. furthermore, upon serumstarvation p53 was seen to translocate to the 11ucleus inNIH 3T3, but not in its mot-2 derivative. The data suggests that mot-2 mediated cytoplasmic sequestration andinactivation of p53 may operate, at least in part, for malignant phenotype of NIH 3T3/mot-2 cells.NIH 3T3/mot-2 cells show inactivation of p53 protein

TRAF2-MLK3 interaction is essential for TNF-α-induced MLK3 activation

Mixed lineage kinase 3 （MLK3） is a mitogen-activated protein kinase kinase kinase that is activated by tumor necrosis factor-α （TNF-α） and specifically activates c-Jun N-terminal kinase （JNK） on TNF-a stimulation. The mecha- nism by which TNF-α activates MLK3 is still not known. TNF receptor-associated factors （TRAFs） are adapter molecules that are recruited to cytoplasmic end of TNF receptor and mediate the downstream signaling, including activation of JNK. Here, we report that MLK3 associates with TRAF2, TRAF5 and TRAF6; however only TRAF2 can significantly induce the kinase activity of MLK3. The interaction domain of TRAF2 maps to the TRAF domain and for MLK3 to its C-terminal half （amino acids 511-847）. Endogenous TRAF2 and MLK3 associate with each other in response to TNF-α treatment in a time-dependent manner. The association between MLK3 and TRAF2 mediates MLK3 activation and competition with the TRAF2 deletion mutant that binds to MLK3 attenuates MLK3 kinase activity in a dose-dependent manner, on TNF-α treatment. Furthermore the downstream target of MLK3, JNK was activated by TNF-α in a TRAF2-dependent manner. Hence, our data show that the direct interaction between TRAF2 and MLK3 is required for TNF-α-induced activation of MLK3 and its downstream target, JNK.

Substantial hepatic necrosis is prognostic in fulminant liver failure

To evaluate if any association existed between the extent of hepatic necrosis in initial liver biopsies and patient survival.METHODSThirty-seven patients with fulminant liver failure, whose liver biopsy exhibited substantial necrosis, were identified and included in the study. The histological and clinical data was then analyzed in order to assess the relationship between the extent of necrosis and patient survival, with and without liver transplantation. The patients were grouped based on the etiology of hepatic necrosis. Each of the etiology groups were then further stratified according to whether or not they had received a liver transplant post-index biopsy, and whether or not the patient survived.RESULTSThe core tissue length ranged from 5 to 44 mm with an average of 23 mm. Causes of necrosis included 14 autoimmune hepatitis, 10 drug induced liver injury (DILI), 9 hepatitis virus infection, and 4 unknown origin. Among them, 11 showed submassive (26%-75% of the parenchymal volume) and 26 massive (76%-100%) necrosis. Transplant-free survival was worse in patients with a higher extent of necrosis (40%, 71.4% and 100% in groups with necrosis of 76%-100%, 51%-75% and 26%-50%, respectively). Additionally, transplant-free survival rates were 66.7%, 57.1%, and 25.0% in groups of autoimmune hepatitis, DILI, and viral hepatitis, respectively. Even after liver transplantation, the survival rate in patients as a result of viral hepatitis remained the lowest (80%, 100%, and 40% in groups of autoimmune hepatitis, DILI, and viral hepatitis, respectively).CONCLUSIONAdequate liver biopsy with more than 75% necrosis is associated with significant transplant-free mortality that is critical in predicting survival.

Performance of FCC Catalyst Improved with Vanadium Trapping Components

The vanadium species were contaminated on FCC catalysts by using the Mitchell method. After the hydrothermal deactivation of the FCC catalysts, the cracking reaction was performed on these catalyst samples. The test results revealed that the conversion of feedstock and the gasoline yield obtained over the FCC catalysts with vanadium trapping components were obviously higher than those without addition of vanadium trapping components. The results also showed that the dry gas and coke selectivity on the FCC catalysts containing vanadium trapping components was improved. The X-Ray diffraction results proved that the zeolite crystal structure was well protected by the vanadium trapping components during its hydrothermal deactivation step. The results of SEM-EDX mapping disclosed that the vanadium was enriched on the vanadium trapping components which verified the positive function of vanadium trapping components.

Enhancement of the Photodynamic Therapy Effect on Streptococcus Mutans Biofilm

Biofilm is a community of bacteria, less susceptible to traditions treatments. Although photodynamic therapy （PDT） is a very effective way to microorganism inactivation, in biofilm it is not as efficient as it is in planktonic bacteria cultures. The increment of an element to increase the effectiveness of PDT was our aim. Therefore, this in vitro study evaluates the susceptibility ofa biofilm formed by Streptococcus mutans on metallic surface of orthodontic accessories under the application of PDT with a surfactant. Samples obtained from blades of orthodontic bands （NiCr）, where used as adhesion surface for the biofilm. They were treated with 1 mg/ml of curcumin, with 0.1% of sodium dodecyl sulfate and exposed to 30 J/cm^2 of light （455 nm）. Eight experimental groups were studied, including the positive and negative controls. The results show that the group with PDT and surfactant had a significant decrease （p 〈 0.001） in viability. In this case, the reduction observed was of 5.6 log10 （CFU/ml） in comparison to the control group. We have shown that, even though the biofilm is very tough and complex structure, we are able to promote almost the complete inactivation ofS. mutans in systems similar to an orthodontic treated patient＇s mouth.

Status and Prospects of Certification Procedure of Novel Pesticides against Major Cocoa Pests Sahlbergella Sngularis and Phytophthora Megakarya in Nigeria

Sahlbergella singularis （brown cocoa mirid） is responsible for over 30% yield loss of cocoa, while Phytophthora megakarya （causal organism of black pod disease） causes between 70-100% yield loss of cocoa in Nigeria. In all the Nigerian cocoa agroecological zones, the use of pesticides still remains an important component among the strategies for effective control of major insect pests and diseases of cocoa. The Cocoa Research Institute of Nigeria （CRIN）, has the national mandate to evaluate and recommend novel pesticides from various groups that fall within the European-Union standards for use on cocoa farms in Nigeria. Such pesticides usually undergo rigorous testing spanning over 3 years to determine correct dose necessary to produce toxic reactions to the targeted pests without any adverse effects on the environment, man and non-target organisms. The screening exercise for candidate pesticides starts with confirmatory test of the constituent active ingredient, laboratory bioassay, phytotoxicity test, first, second and third year field evaluation and residue analysis of beans harvested from the treated plots. This paper critically examines these standard procedures, which must be followed judiciously for novel pesticides certification and recommendation for use in Nigeria.

What Is Important in Selecting Phlebiopsis gigantea Strain for Commercial Use？

Phlebiopsis gigantea strains registered in the European Union as biocontrol agents against root rot in forests （four from Great Britain and two from Finland） were compared using Ward＇s method with reference to： （l） similarity of DNA-random amplified microsatellite （RAMS） ladders, （2） cellulase and peroxidase production and （3） acceleration of dry mass wood loss in Norway spruce The activity of the enzymes was tested in the initial phase of wood decay （30 d after inoculation） and indicated as the most active isolates： VFI0 and FCl5 for cellulase and FC16 and VFI0 for peroxidase production. The assessment of loss of wood six months after inoculation indicated isolate FC 15 as the most active. P. gigantea isolates similar in terms of enzyme activity indicated different patterns ofDNA microsatellite loci. At the same time, DNA-RAMS revealed similarities in isolates with different abilities to produce enzymes. However, some similarities and differences between isolates according to wood decay were found. No plain relationships between molecular characteristics and enzyme activity of the strains tested were observed. The results differentiated activity of tested isolates and suggested benefits of selecting P. gigantea strains for commercial use basing mainly on the assessment of wood loss activity.

特发性肾性低尿酸血症相关的运动诱发急性肾衰竭一例

特发性肾性低尿酸血症是一种罕见的常染色体隐性遗传的肾小管疾病，因编码肾小管尿酸转运子的基因出现失活性突变，造成肾小管对尿酸的转运功能受损，尿酸重吸收减少和（或）排泄增多，从而引起低尿酸血症。

Loss of silencing activity caused by 5′-terminal modification with D-/L-isonucleotide(isoNA) or locked nucleic acid(LNA) could not be restored by 5′-terminal phosphorylation

In this study,a series of 5′-phosphorylated siRNAs with D-/L-isonucleotide(isoNA)or locked nucleic acid(LNA)incorporated at the 5′-terminus were synthesized.It was found that after incorporating either isoNA or LNA at the 5′-terminus of the antisense strand or sense strand,the silencing activity of modified strands has been inhibited,which cannot be recovered by phosphorylation at the 5′-terminus;however,the silencing activity of unmodified strand to its own target was increased.This work indicates that the isoNA and LNA modification at 5′-terminus can interfere with the strand selection during the RISC assembling process,and the disturbance of the 5′-phosporylation should not be the only viable mechanism.

Self-extinguishing Janus separator with high safety for flexible lithium-sulfur batteries

Flexible lithium-sulfur(Li-S)batteries are considered one of the most promising candidates for highenergy-density storage devices in wearable electronics.However,the safety problem severely restricts the practical application of Li-S batteries because of the possible occurrence of thermal runaway caused by battery short circuits and combustible components,particularly under bending conditions.The development of advanced separators that can suppress lithium dendrite growth and are incombustible is the key to improving the safety of flexible Li-S batteries.In this work,a nonflammable multifunctional Janus separator with self-extinguishing capability,high thermal stability,high thermal conductivity,good electrolyte infiltration,uniform lithium deposition,and efficient polysulfide shuttling inhibition,is proposed.The separator is composed of polyacrylonitrile(PAN)fiber and decabromodiphenyl ethane(DBDPE)membrane as well as functional layers of boron nitride(BN)for suppressing lithium dendrite growth and reduced graphene oxide(rGO)for accelerating the sulfur convention kinetics.As a result,the Li-S battery with a sulfur mass loading of2.7 mg cm^(-2) delivers a specific capacity of 916.8 mA h g^(-1) after100 cycles at 0.1 C and maintains a stable performance during intermittent thermal shock.Moreover,the Li-S pouch cell with a sulfur mass loading of 8 mg exhibits a high capacity of6.3 mA h under bending conditions.