CALCULATION METHODS ON CRACK RESISTANCE CAPACITY OF CONNECTION COMPOSED OF CSSEUHSC COLUMNS AND SEC BEAMS

In order to investigate the calculation methods on crack resistance capacity of connection composed of cross shaped steel encased ultra high strength concrete (CSSEUHSC) columns and steel encased concrete (SEC) beams under cycle loads, six interior connection specimens were tested in the laboratory. A discussion on the crack resistance capacity was presented. Calculation methods of crack resistance capacity were deduced based on the experimental case and calculation results were in good agreement with the experimental results. The research results indicated that parameters of connection composed of CSSEUHSC columns and SEC beams with better crack resistance performance may be referred for engineering application.     

PFOS对哈维氏弧菌生长及外毒素基因的影响

探讨了全氟辛烷磺酸盐(PROS)对哈维氏弧菌密度及外毒素基因表达的影响.用含有不同浓度PFOS(5、50、500 mmol/L)的培养基培养哈维氏弧菌,分别在6、15、24 h取适量菌液,经4 000 r/min离心,磷酸盐缓冲液(PBS)洗涤3次,制成PBS菌悬液.采用实时荧光定量PCR检测其胞外蛋白酶、溶血素及保守...     

聚乙二醇对哈维氏弧菌疫苗免疫效果的影响

以聚乙二醇( PEG)作为超声介质及疫苗载体,用超声波瞬间高温、高压及剪切力作为灭活方式,将哈维氏弧菌制成PEG结合疫苗,该疫苗与传统疫苗分别经腹腔注射免疫接种锦鲤成鱼,检测了锦鲤血细胞吞噬百分率、吞噬指数、抗菌活力、抗体效价及免疫保护力等指标,评价疫苗效果.结果表明,PEG6000作为载体制备的疫苗,其各指标统计比较...     

Isolation and Crystallographic Characterization of the Labile Isomer of Y@C82 Cocrystallized with Ni(OEP): Unprecedented Dimerization of Pristine Metallofullerenes

Although the major isomers of M@C₈₂ (namely M@C_2v(9)‐C₈₂, where M is a trivalent rare‐earth metal) have been intensively investigated, the lability of the minor isomers has meant that they have been little studied. Herein, the first isolation and crystallographic characterization of the minor Y@C₈₂ isomer, unambiguously assigned as Y@C_s(6)‐C₈₂ by cocrystallization with Ni(octaethylporphyrin), is reported. Unexpectedly, a regioselective dimerization is observed in the crystalline state of Y@C_s(6)‐C₈₂. In sharp contrast, no dimerization occurs for the major isomer Y@C_2v(9)‐C₈₂ under the same conditions, indicating a cage‐symmetry‐induced dimerization process. Further experimental and theoretical results disclose that the regioselective dimer formation is a consequence of the localization of high spin density on a special cage‐carbon atom of Y@C_s(6)‐C₈₂ which is caused by the steady displacement of the Y atom inside the C_s(6)‐C₈₂ cage.     

Crystallographic Evidence for Direct Metal–Metal Bonding in a Stable Open‐Shell La2@Ih‐C80 Derivative

Endohedral metallofullerenes (EMFs) have novel structures and properties that are closely associated with the internal metallic species. Benzyl radical additions have been previously shown to form closed‐shell adducts by attaching an odd number of addends to open‐shell EMFs (such as Sc₃C₂@I_h‐C₈₀) whereas an even number of groups are added to closed‐shell EMFs (for example Sc₃N@I_h‐C₈₀). Herein we report that benzyl radical addition to the closed‐shell La₂@I_h‐C₈₀ forms a stable, open‐shell monoadduct instead of the anticipated closed‐shell bisadduct. Single‐crystal X‐ray diffraction results show the formation of a stable radical species. In this species, the La?La distance is comparable to the theoretical value of a La?La covalent bond and is shorter than reported values for other La₂@I_h‐C₈₀ derivatives, providing unambiguous evidence for the formation of direct La?La bond.     

Regioselective Synthesis,Crystallographic Characterization,and Electrochemical Properties of Pyrazole- and Pyrrole-Ring-Fused Derivatives of Y2@C3v(8)-C82

Chemical modification of endohedral metallofullerenes (EMFs) is an efficient strategy to realize their ultimate applications in many fields. Herein, we report the highly regioselective and quantitative mono-formation of pyrazole- and pyrrole-ring-fused derivatives of the prototypical di-EMF Y₂@C_3v(8)-C₈₂, that is, Y₂@C_3v(8)-C₈₂(C₁₃N₂H₁₀) and Y₂@C_3v(8)-C₈₂(C₉NH₁₁), from the respective 1,3-dipolar reactions with either diphenylnitrilimine or N-benzylazomethine ylide, without the formation of any bis- or multi-adducts. Crystallographic results unambiguously reveal that only one [6,6]-bond out of the twenty-five different types of nonequivalent C−C bonds of Y₂@C_3v(8)-C₈₂ is involved in the 1,3-dipolar reactions. Our theoretical results rationalize that the remarkably high regioselectivity and the quantitative formation of mono-adducts are direct results from the anisotropic distribution of π-electron density on the C_3v(8)-C₈₂ cage and the local strain of the cage carbon atoms as well. Interestingly, electrochemical and theoretical studies demonstrate that the reversibility of the redox processes, in particular the reversibility of the reductive processes of Y₂@C_3v(8)-C₈₂, has been markedly altered upon exohedral functionalization, but the oxidative process was less influenced, indicating that the oxidation is mainly influenced by the internal Y₂ cluster, whereas the reduction is primarily associated with the fullerene cage. The pyrazole and pyrrole-fused derivatives may find potential applications as organic photovoltaic materials and biological reagents.     

WPU/Cu2-XSe coated cotton fabrics for photothermal conversion and photochromic applications

Cellulose - Multifunctional cotton fabrics were fabricated by coating of anionic waterborne polyurethane (WPU)/Cu2-XSe. The surface morphology of WPU/Cu2-XSe coated cotton fabric was characterized...     

Effects of Melatonin on Dairy Herd Improvement (DHI) of Holstein Cow with High SCS

Mastitis is a common disease in cows breeding. The milk quality will be significantly reduced with increased milk somatic cells, which often occurs in cows with mastitis. In this study, the influence of seasonal changes, age and lactation stages in the Dairy Herd Improvement (DHI) of cows was investigated. Then, the Dairy Herd Improvement (DHI) of cows with high somatic cell score (SCS) after melatonin treatment was systemically investigated. The results showed that melatonin significantly suppressed the milk somatic cell score under all of the tested conditions. The melatonin treatment also improved the milk nutritional value by reducing its fat but increasing its lactose and protein contents. The application of melatonin significantly improved the DHI. The beneficial effects of melatonin on DHI are likely attributed to the antioxidant and anti-inflammatory activities of melatonin.