Regio- and Enantioselective Allylic Cyanomethylation by Synergistic Rhodium and Silane Catalysis.

Rh/silane-cocatalyzed regio- and enantioselctive allylic cyanomethylation with inert acetonitrile directly has been developed. Addition of a catalytic amount neutral silane reagent as an acetonitrile anion carrier is essential for the success of this reaction. The synthesis of mono- and bis-allylation products can be switched by adjusting the size of substituents on the silane, ligands, and temperature. Chiral homoallylic nitriles could be synthesized in above 20:1 branch/linear ratio, up to 98% yield and >99% ee.

Key factors impacting treatment efficiency in actual copper mineral processing wastewater by ozonation.

Ozone advanced oxidation has been widely used in water treatment, but little research has been reported on the application of ozone to difficult-to-degrade mineral wastewater. In this paper, the effect of ozonation application in the treatment of copper mineral processing wastewater, which is difficult to be effectively treated by traditional processes due to its complex composition, was investigated. The effects of ozonation time, ozone concentration, temperature and pH on the degradation of organic compounds in the wastewater by ozonation were researched. It was found that the chemical oxygen demand (COD) of the wastewater could be reduced by 83.02% by ozonation under optimal treatment conditions. In addition, the mechanism of ozone degradation of the difficult-to-degrade wastewater was studied, and the reasons for the fluctuating variations of COD and ammonia nitrogen during ozonation treatment were explained.

Enantioselective Synthesis of Pyridines with All-Carbon Quaternary Carbon Centers via Cobalt-Catalyzed Desymmetric [2+2+2] Cycloaddition.

A Co-catalyzed enantioselective desymmetric [2+2+2] cycloaddition for synthesis of pyridines with all-carbon quaternary carbon centers has been developed. The regio- and enantioselectivities are controlled by the inherent nature of terminal alkynes and the substituents on the bisoxazolinephosphine ligands. Pyridines with 5-substitutents could be obtained with >20:1 regioselectivity and up to 94 % ee when terminal alkyl, alkenyl or silyl alkynes and DTBM/Ph-based NPN* ligand L6 were used. Terminal aryl alkynes and Ph/Bn-based ligand L4 leads to formation of pyridines with 6-substitutents in up to 99 % ee.

Short-time ozone treatment promotes protease-mediated destruction of B cell allergen epitopes by altering the structural characteristics of whey protein.

A novel processing method combining short-time ozone pretreatment with hydrolysis has been developed to reduce whey protein allergenicity. The results showed that ozone treatment altered the whey protein spatial structure, initially increasing the surface hydrophobicity index, and then decreasing due to polymer formation as the time increased. Under the optimized conditions of alkaline protease-mediated hydrolysis, a 10-second pre-exposure to ozone significantly promoted the reduction in the IgE binding capacity of whey protein without compromising the hydrolysis efficiency. Compared with whey protein, the degranulation of KU812 cells stimulated by this hydrolysate decreased by 20.54%, 17.99%, and 22.80% for IL-6, ß-hexosaminidase, and histamine, respectively. In vitro simulated gastrointestinal digestion confirmed increased digestibility and reduced allergenicity. Peptidomics identification revealed that short-time ozonation exposed allergen epitopes, allowing alkaline protease to target these epitopes more effectively, particularly those associated with α-lactalbumin. These findings suggest the promising application of this processing method in mitigating the allergenicity of whey protein.

Degradation characteristics of p-nitrophenol and atenolol by carbon nitride modified by graphene quantum dots.

Photocatalysis is a promising technology for wastewater treatment. It is of great significance to find catalysts with high photoactivity. In this paper, a catalyst with high photocatalytic degradation efficiency to organic wastewater, carbon nitride modified by graphene quantum dots (SCN-GQDX), is prepared by supramolecular self-assembly thermal polycondensation method and doping graphene quantum dots (GQDs). The results show that SCN-GQD0.5 has the best catalytic performance, and its photocatalytic degradation efficiency to organic pollutants can reach 86% and still remains above 83% after five cycles, which shows the modified carbon nitride has high catalytic efficiency and stability. In a word, SCN-GQDX is a highly efficient, non-toxic and stable photocatalyst for organic pollutants in wastewater.

Left thoracoabdominal approach in surgical treatment of adenocarcinoma of the esophagogastric junction in the Northern Henan Province of China.

BACKGROUND: The left thoracoabdominal (LTA) approach is the conventional way to treat adenocarcinoma of the esophagogastric junction (EGJ). The study was to review the outcome of the LTA approach with adenocarcinoma of the EGJ in a single institution in China. METHODS: 135 consecutive adenocarcinomas of EGJ patients who underwent surgical treatment were retrospectively analyzed; data gathered included basic information on the tumor, surgical approach, postoperative complications and survival rate. RESULTS: LTA esophagogastrectomy was performed in all patients. No patients received allogeneic blood transfusion during the operation. Among the resective procedures, proximal gastrectomy was performed in 122 cases. The mean operation time was 150 min (90-240). R(0) resection was obtained in 120 patients (88.9%). Two patients developed respiratory failure 2 days after surgery. Contrast swallow revealed a leak at the anastomosis in 2 patients. One early anastomotic stricture was observed radiologically, and pneumonia was observed in 3 patients. The number of patients with spontaneous pneumothorax and wound infections were 3 and 5, respectively. The percentage was zero in-hospital deaths. The overall survival rates at 1 year and 2 years were 89.2 and 69%, respectively. The median survival was 27.1 months. CONCLUSION: LTA esophagogastrectomy has a major role in the management of adenocarcinoma of the EGJ, at least in the northern Henan Province of China.

Predictions of Entropy and Gibbs Energy for Carbonyl Sulfide.

Many chemical and physical equilibrium conditions can be determined from minimizing the Gibbs free energies of the system. Efficient analytical representations of the entropy and Gibbs free energy of carbonyl sulfide remain elusive in the communality of science and engineering. Here, we report two analytical representations of the entropy and Gibbs free energy for carbonyl sulfide, and the prediction procedures only involve six molecular constants of the carbonyl sulfide molecule. In the temperature range from 300 to 6000 K, the average relative deviations of the predicted molar entropy and reduced Gibbs free energy values of carbonyl sulfide from the National Institute of Standards and Technology database are arrived at 0.150 and 0.189%, respectively.