Neighboring Platinum Atomic Sites Activate Platinum-Cobalt Nanoclusters as High-Performance ORR/OER/HER Electrocatalysts.

The rational design of efficient and multifunctional electrocatalysts for energy conversion devices is one of the major challenges for clean and renewable energy transition. Herein, the local electronic structure of cobalt-platinum nanoclusters is regulated by adjacent platinum atomic site encapsulated in N-doped hollow carbon nanotubes (PtSA -PtCo NCs/N-CNTs) by pyrolysis of melamine-orientation-induced zeolite imidazole metal-organic frameworks (ZIF-67) with thimbleful platinum doping. The introduction of melamine can reactivate adjacent carbon atoms and initiate the oriented growth of nitrogen-doped carbon nanotubes. The systematic analysis suggests the significant role of thimbleful neighboring low-coordinated Pt─N2 in altering the localized electronic structure of PtCo nanoclusters. The optimized PtSA -PtCo NCs/N-CNTs-900 exhibit excellent hydrogen evolution reaction (HER)/oxygen evolution reaction (OER)/oxygen reduction reaction (ORR)/ catalytic performance reaching the current density of 10 mA cm-2 in 1 m KOH under the low 47 (HER) and 252 mV (OER) overpotentials, and a high half-wave potential of 0.86 and 0.89 V (ORR) in 0.1 m KOH and 0.1 m HClO4 , respectively. Remarkably, the PtSA -PtCo NC/N-CNT-900 also presents outstanding catalytic performances toward water splitting and rechargeable Zn-air batteries. The theoretical calculations reveal that optimal regulation of the electronic structure of PtCo nanoclusters by thimbleful neighboring Pt atomic reduces the reaction energy barrier in electrochemical process, facilitating the ORR/OER/HER performance.

[Comparative study of the protective effect of Xuebijing injection and Sivelestat sodium on acute lung injury/acute respiratory distress syndrome rats].

OBJECTIVE: To compare the protective effect of Xuebijing injection versus Sivelestat sodium on acute lung injury/acute respiratory distress syndrome (ALI/ARDS) rats. METHODS: A total of 71 male Sprague-Dawley (SD) rats were randomly divided into the blank control group (n = 8), ALI/ARDS model group (n = 21), Xuebijing injection group (n = 21) and Sivelestat sodium group (n = 21). Rats in the blank control group were injected with normal saline while the other three groups were intravenously injected 25 mg/kg lipopolysaccharide (LPS) via the tail vein to establish ALI/ARDS model. After induction of ALI/ARDS model, the blank control group and ALI/ARDS model group were given intraperitoneal injection of an equal volume of normal saline twice a day. Rats in the Xuebijing injection group were given tail vein injection of 8 mL/kg Xuebijing injection twice a day, and those in the Sivelestat sodium group were given intraperitoneal injection of 100 mg/kg Sivelestat sodium three times a day. All rats were administered continuously for five days. During the experiment, the general status of rats was observed, and the weight and survival were recorded. At the end of the experiment, bronchoalveolar lavage fluid (BALF) of rats was collected for the detection of inflammatory cells and inflammatory factors. Histopathological changes of rats lung tissue were observed. RESULTS: Compared with the ALI/ARDS model group, the Xuebijing injection group and Sivelestat sodium group had significantly decreased white blood cell (WBC) count and percent of neutrophil (NEU%) [WBC (×109/L): 55.86±6.68, 49.96±6.76 vs. 73.13±7.35, NEU%: 0.459±0.077, 0.315±0.047 vs. 0.709±0.067, all P < 0.05], significantly increased percent of lymphocytes (LYM%: 0.412±0.067, 0.517±0.051 vs. 0.232±0.057, both P < 0.05), and reduced interleukin-6 (IL-6) level (ng/L: 295.2±39.7, 281.9±33.1 vs. 469.6±77.0) in BALF. However, there were no significant differences in these parameters between the Xuebijing injection group and Sivelestat sodium injection group (all P > 0.05). Survival rate at the end of experiment was higher in the Xuebijing group than that in the Sivelestat sodium injection group and ALI/ARDS model group [52.4% (11/21) vs. 28.6% (6/21), 14.3% (3/21)], and survival rate at the end of experiment was higher in the Sivelestat sodium injection group than that in the ALI/ARDS model group, but the differences were not statistically significant (P > 0.05). In addition, weight and weight growth rate in the Xuebijing injection group were higher than the Sivelestat sodium group at the end of the experiment [weight (g): 217.1±6.4 vs. 207.1±7.0, weight growth rate: (-0.9±2.8)% vs. (-4.3±3.5)%], there were no significant difference between the two groups (both P > 0.05). Lung histopathology in the ALI/ARDS model group revealed high level of inflammatory exudate and inflammatory cells infiltrated in the alveoli of rats, along with damage of local alveolar epithelial cell and alveolar structure. However, these histological changes were improved in the Xuebijing injection group and in the Sivelestat sodium group. CONCLUSIONS: Xuebijing injection can alleviate ALI/ARDS-induced lung injury and systemic damage and improve the survival of rats by inhibiting inflammation. The protective effect of Xuebijing injection is essentially consistent with that of Sivelestat sodium.

Grating-tuned dual-wavelength Nile red dye laser.

Dual-wavelength operation of grating-tuned dye laser systems was demonstrated in this paper. We used the second harmonic generation of a Q-switched Nd:YAG laser to pump the Nile red solvent (dissolved in ethanol) in the Littrow configuration and the Littman-Metcalf configuration. By rotating the grating 3.6° in the Littrow configuration and the tuning mirror 3.9° in the Littman-Metcalf configuration, we obtained a 72 and 46 nm tuning-range dye laser output, respectively. Meanwhile by parallelly moving the grating in the Littrow configuration and the tuning mirror in the Littman-Metcalf configuration, we achieved the separation of dual wavelength from 0.7 to 5 nm in the former and 1.5 to 4 nm in the latter, which were in the terahertz range and could find applications in the terahertz source after using difference frequency technology. Finally, after considering the laser trajectories in the two configurations, we theoretically analyzed the reasons for overall tuning and separation tuning of dual wavelength.

Pharmacokinetics of sifuvirtide in treatment-naive and treatment-experienced HIV-infected patients.

The pharmacokinetics assessment in two clinical studies of sifuvirtide (a novel HIV fusion inhibitor) was first reported in Chinese HIV patients. Nineteen treatment-naive HIV patients were treated with s.c.(subcutaneous injection) sifuvirtide [10 or 20 mg q.d.(quaque die)] for 28 days in study 1, and eight treatment-experienced HIV patients were treated with s.c. sifuvirtide (20 mg q.d.) in combination with HAART drugs (lamivudine, didanosine, and Kaletra) for 168 days in study 2. In study 1, T1/2 was 17.8 ± 3.7 h for 10 mg group and 39.0 ± 3.5 h for 20 mg group; the mean Cmax of last dose was 498 ± 54 ng/mL for 10 mg group and 897 ± 136 ng/mL for 20 mg group. In study 2, T1/2 was 6.71 ± 2.17 h in treatment-experienced patients. Cmax was 765 ± 288 ng/mL after last 168th dosage. Sifuvirtide showed improved clinical pharmacokinetics characteristics compared with Enfuvirtide, and showed very different pharmacokinetic characteristics between treatment-naive and treatment-experienced patients. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association J Pharm Sci 103:4038-4047, 2014.