Study on the Effect of Shuanghuanglian Powder Needle Combined with Cefoperazone and Sulbactam Sodium on Pseudomonas aeruginosa in Vitro

Objective: To explore the antibacterial activity of combined use of Shuanghuanglian and cefoperazone sulbactam sodium on resistant strains of Pseudomonas aeruginosa. Methods: The Pseudomonas aeruginosa strains which were sensitive and resistant to cefoperazone sulbactam sodium were selected to prepare different test bacterial solutions respectively;The experimental liquid of Shuanghuanglian and Cefoperazone Sulbactam Sodium were prepared separately and set as different test groups and control groups;The Drug Sensitivity Tests of Shuanghuanglian and cefoperazone sulbactam sodium at different concentration gradients which were used alone or used in combination were carried out for different strains with sensitivity and resistance, And use standard entry as a reference control. Result: The results of drug sensitivity test of Shuanghuanglian combined with Cefoperazone-Sulbactam sodium against the resistant strains of Pseudomonas aeruginosa were compared with the results of drug sensitivity test of the two separately used, and the difference was statistically significant (P 〈 0.05) [The drug sensitivity test results of Shuanghuanglian and cefoperazone sulbactam sodium to Pseudomonas aeruginosa resistant strains were statistically significant compared with the drug sensitivity test results of Shuanghuanglian and Cefoperazone Sulbactam Sodium used separately (P 〈 0.05)];There was a dependence between strains and concentration in the effect of the combination of the two drugs. Conclusion: The combination of Shuanghuanglian and cefoperazone sulbactam sodium has synergistic antibacterial or bactericidal effect on Pseudomonas aeruginosa resistant strains. .

Some Advances in the Application of Weathering and Cold-Formed Steel in Transmission Tower

Application of weathering and cold-formed steel in transmission lines can reduce steel consumption and environmental pollution. Some advances in the studies on the weathering and cold-formed steel in transmission tower are introduced. Firstly, corrosion-resistant tests of weathering steel samples under different simulating technical atmospheres were carried out separately for 240 hours. It shows that the corrosion degree of joint samples is higher than that of single chip samples, and the corrosion-resistant performance of weathering steel is superior to common carbon steel. The corrosion-resistance of weathering steel meets with the requirement of transmission tower. Secondly, experiments and finite element analysis for cold-formed angles and a 220kV prototype tower were completed, and the stability coeffi-cient fitting curves as well as the modification formulas of slenderness ratio for cold-formed members were determined. According to the structural characteristics of transmission towers, four sections of cold-formed angles with different sections and slenderness ratios were selected in this study. The finite element model well predicted the buckling behav-iour of the cold-formed members. Ultimate loads calculating by the fitting curve were well agreed to the experimental values, especially for the members with small slenderness ratios. Weight of the cold-formed steel tower can be reduced by more than 5 percent after considering the strength enhancement. Cost of the weathering and cold-formed steel transmission tower is nearly equivalent to that of hot-rolled steel tower with hot galvanizing.

Facile oxalic acid-assisted construction of laminated porous N-deficient graphitic carbon nitride: Highly efficient visible-light-driven hydrogen evolution photocatalyst

The laminated porous N-deficient g-C3N4(CN–H)is successfully synthesized by a facile two-step hydrothermal calcination method using oxalic acid-assisted melamine as the precursor.Compared with pristine g-C3N4(224μmol g-1h-1),the CN–H shows superior photocatalytic hydrogen production activity(up to 728μmol g-1h-1),which is three times higher than the unmodified counterpart.To draw out the multifaceted influences of oxalic acid modification on the visible-light-induced photocatalytic activity,various techniques are utilized to investigate the formation mechanism,structural characteristics and photoelectrical properties of CN–H.The results indicate that the addition of a trace amount of oxalic acid to the precursor melamine results in a g-C3N4 structure possessing the advantage of both nitrogen defects and laminated porosity.These properties can enlarge specific surface areas of g-C3N4,enhance an efficient separating of photogenerated electron-hole pairs and extend the range of spectral response,all contributing to the enhancement of the visible-light-induced photocatalytic activity.

Facile construction of highly efficient MOF-based Pd@UiO-66-NH_(2)@ZnIn_(2)S_(4)flower-like nanocomposites for visible-light-driven photocatalytic hydrogen production

Construction of metal-organic-frame works-based composite photocatalysts has attracted much attention for the reasonable band gap and high surface areas to improve the photocatalytic activity.In this study,the ternary heterojunction Pd@UiO-66-NH_(2)@ZnIn_(2)S_(4)nanocomposites were facilely prepared for the first time by a two-step method.The visible-light-promoted hydrogen production rate of 0.3%Pd@UiO-66-NH_(2)@ZnIn_(2)S_(4)reaches up to 5.26 mmol g^(-1)h^(-1),which is evidently much higher than pure UiO-66-NH_(2),ZnIn_(2)S_(4)and binary UiO-66-NH_(2)/ZnIn_(2)S_(4)composites.Such a huge improvement in the photocatalytic performance is mainly attributed to the matched band gap of ZnIn_(2)S_(4)and UiO-66-NH_(2),and the introduction of Pd NPs into photocatalysts that broaden spectral response range and promote the photon induced charge carrier separation.This work may provide a feasible approach for the design and construction of metal-organic-frameworks-based photocatalytic materials.

Synthesis and photoluminescent properties of Sm^(3+)-activated La_(3)Si_(6)N_(11)as an orange-red emitting phosphor

A series of Sm^(3+)-doped La_(3)Si_(6)N_(11)phosphor materials we re synthesized by a high temperature solid-state reaction method.The crystal structure,micro structure,photoluminescence properties,decay curves as well as thermal quenching properties of the as-prepared phosphors were investigated systematically.The excitation spectra contain a wide asymmetric band below 350 nm originating from the host absorption,several sharp excitation peaks in the range of 300-550 nm corresponding to f-f transition of Sm^(3+).Under the excitation of 369 and 414 nm light,the phosphors exhibit strong narrow-band orangered emission peaked at 605 nm.The average decay time of La_(2.99)Si_(6)N_(11):0.01 Sm^(3+)sample is fitted to be0.38 ms and the CIE coordinates were calculated to be(0.6105,0.3833).For water resistance,La_(3)Si_(6)N_(11):Sm^(3+)is better than K_(2)SiF_(6):Mn^(4+)phosphor.After soaking in deionized water for 300 min,the La_(3)Si_(6)N_(11):Sm^(3+)sample retains approximately 80%of its initial relative emission intensity.When the temperature rises to 423 K(150℃),the emission intensity of La_(2.99)Si_(6)N_(11):0.01 Sm^(3+)sample remains 85%in co mparison to that of room tempe rature.The activation energy was calculated to be 0.63253 eV,which is higher than those of Sm^(3+)-activated oxide phosphors,indicating that the phosphor has relatively good thermal stability.

Electroless-hydrothermal construction of nickel bridged nickel sulfide@mesoporous carbon nitride hybrids for highly efficient noble metal-free photocatalytic H2 production

Metallic Ni bridged Ni S@mesoporous carbon nitride hybrids were for the first time fabricated through a one-pot electroless-assisted hydrothermal method.The intimate Ni bridge between the interface of mesoporous carbon nitride and Ni S was confirmed by HRTEM and in-depth XPS analysis using an Ar+-cluster sputtering gun and a possible mechanism was put forward to elucidate the formation process of the unique structure.Without adding any noble metals as cocatalysts,the optimized catalyst 10%NiS/mCN-160-12 showed a H2 evolution rate of 1419μmol·g^-1·h^-1,which is about 34 and 14 fold higher than that of bare mesoporous carbon nitride and Ni S,respectively.The dramatically enhanced photocatalytic performance was mainly ascribed to the synergistic effect of Ni S cocatalyst loading and the formation of metallic Ni between the interface of mesoporous carbon nitride and Ni S,which served as a charge-transfer bridge to facilitate the transfer and separation of photo-induced electron-hole pairs.