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A general strategy for developing nitro compounds hydrogenation catalysts, involving constructing interfaces of transition-metal compounds with nitrogen-doped carbon, is proposed. The interfacial bonds in the developed catalysts can modulate the electronic structure of active sites, and hence significantly expose the active sites and enhance mass transport. Specifically, optimal Cr2O3/NC, Mo2C/NC, V2O3/NC and WOx/NC catalysts provide impressive performances with a conversion rate of 99% and a nearly 100% selectivity for hydrogenating nitro compounds. [ABSTRACT FROM AUTHOR]

As-synthesized Cu3PdN nanocrystals displayed high faradaic efficiency and selectivity for nitrate-to-ammonia conversion. The excellent performances can be attributed to the charge redistribution in Cu3PdN as a result of modulations of the electronic structures of Pd and Cu atoms, which altered the adsorption activation energy of the intermediates during the nitrate reduction reaction process. [ABSTRACT FROM AUTHOR]

Abstract: A steady-state model of the coaxial parallel-type drive system is established to discuss the matching relations between the drive system and the dynamic load of the compressor. In order to improve energy conversion efficiency, this paper raises a torque control model, establishes the optimization scheme of the drive system and puts forward the switching law of the Hybrid-power Gas Engine Heat Pump (HPGHP). In addition, a new method of transmission ratio design is put forward to optimize the power matching of the drive system based on the load model of probability distribution. The simulation results show that the transmission ratios are respectively 3.2, 2 and 1.5 in three modes. At last, the energy management scheme of battery packs has been established. The results show that the state of the charge (SOC) can keep constant in one cycle when the ratio between the Mode L operation time and the Mode C operation time is about 1.38. And the variation range of SOC depends on the operation time of Mode D in one cycle. [Copyright &y& Elsevier]

In this work, the formed interfacial Co–O–Cu bonds in Co-doped Cu(OH)2 (Co2–Cu(OH)2) sufficiently expose active sites and improve the reaction kinetics. As a result, the optimal Co2–Cu(OH)2 provides an amazing faradaic efficiency (91.6%), high selectivity (93.2%) and robust stability toward the NO3RR. [ABSTRACT FROM AUTHOR]

Objectives. To summarize the clinical manifestations, diagnosis, treatment, and prognosis for inferior oblique muscle ectopia (IO-E). Subjects and Methods. Patients diagnosed with IO-E during strabismus surgery from March 2017 to September 2018 were included in this retrospective, cross-sectional study. All patients received preoperative Krimsky test, synoptophore, cycloplegia refraction, fundus torsion, and other strabismus-related specific tests. The anatomic variations of IO-E were always discovered during surgical procedure. Postoperative eye position and binocular visual function (BVF) were all reviewed in early days after operation. Results. A total of 7 patients were enrolled in this study with an average age of 6.4 ± 3.8 yrs. They all presented with significant exotropia and unilateral (or bilateral) overelevation in adduction (OEA). No compensatory head position was detected. Some of them had vertical deviation, V pattern, or excyclotropia, which were indicated by fundus torsion. Monocular or binocular IO-E was distinguished during the surgery, and it could be classified into two types according to its anatomic features. In surgery, the ectopic IO muscle bundle was restored, and different IO weakening methods were employed. Meanwhile, the horizontal deviation was also corrected according to the preoperative examination. Eyes of all patients were properly aligned in the primary position after surgery. Varying degrees of BVF appeared in 3 cases. Conclusions. IO-E is a rare congenital dysplasia variation of the extraocular muscle, which could appear as inferior oblique overaction. It is difficult to diagnose before surgery, and weakening the overactive ectopic inferior oblique was required for better prognosis if this condition was confirmed during surgery. [ABSTRACT FROM AUTHOR]

Hybrid-power gas engine heat pump (HPGHP) combines hybrid power technology with gas engine heat pump, which can keep the gas engine working in the economical zone. In this paper, a steady-state model of the HPGHP in heating condition has been established, the optimal torque curve control strategy is proposed to distribute power between the gas engine and battery pack. The main operating parameters of the HPGHP system are simulated on Matlab/Simulink and validated by experimental data, such as operating temperature, coefficient of performance (COP), fuel-consumed rate, etc. Heating capacity and COP of the heating pump system are validated under different ambient temperatures and water flow rates. The simulation and experiment results shows acceptable agreement, the maximum difference is respectively 8.9%, 5.9%, 9.5% and 8.2% for engine torque, motor torque, reclaimed heat and fuel-consumed rate. Based on the simulation results, HPGHP has the lowest fuel-consumed rate of 283 g (kWh) −1 at engine speed of 3000 rpm; the PER of HPGHP system is about 15.9% and 11.4% higher than the GHP under the same load in Mode C and D. [ABSTRACT FROM AUTHOR]

Aims: Wavefront aberration (WA) has become one of the important indicators for measuring the visual quality. Whether strabismus surgery affects the WA remain controversial. This study aims to investigate the postoperative alterations of WA in patients who underwent horizontal rectus muscle surgery. Methods: A total of 34 patients were enrolled and divided into two groups: bilateral lateral rectus recession (BLR) group and unilateral lateral rectus recession and medial rectus resection (R&R) group. The WA was examined 1 day before surgery, 3 days, and 6 weeks after surgery using the iTrace Visual Function Analyzer (Tracey Technologies). Results: Significant increases in total WA, lower-order aberration (LOA) and higher-order aberration (HOA) of both groups were detected in 3 days after surgery (P < 0.05), while no significant differences in 6 weeks after surgery. Significant increases in astigmatism, secondary astigmatism, and trefoil of both groups were detected in 3 days after surgery (P < 0.05), while no significant differences in individual order of LOA and HOA in 6 weeks postoperatively. Z22, Z33, and Z42 of both groups increased significantly 3 days after surgery (P < 0.05) and returned to baseline level 6 weeks after surgery, while the rest Zernike coefficients remained the same postoperatively. When comparing the differences between the two groups, there were no statistically significant differences in these parameters between baseline and each follow-up visit postoperatively. Conclusions: The increase of WA restored to pre-operative level in 6 weeks after surgery, indicating the influences of horizontal rectus muscle surgery to WA were transient and reversible. [ABSTRACT FROM AUTHOR]

Developing nonprecious catalysts with excellent behaviors for oxygen reduction reaction (ORR) has assumed considerable importance, but remains an arduous issue. Herein, we demonstrate a Kirkendall effect-pyrolysis (KEP) strategy to construct N-bridged Cu-Zn dual-atom supported on hollow N-doped carbon (Cu-Zn DA/HNC) for ORR. The hollow structure of N-doped carbon facilitates mass transfer and exposes more actives. What's more, the shared N atom between Cu and Zn atoms is beneficial to enhance their synergetic effect, creating an appropriately enhanced O* binding. The resulting Cu-Zn DA/HNC displays excellent ORR activity in an alkaline electrolyte, following a nearly four-electron pathway of ORR. Even employing Cu-Zn DA/HNC as the cathode in ZABs, Cu-Zn DA/HNC presents a long cycling life up to 910 h and robust low-temperature adaptability. The facile and straightforward fabrication plus the outstanding ORR performance of Cu-Zn DA/HNC endows its great potential as a significant candidate in practical applications of ZAB. [Display omitted] • Nitrogen-bridged Cu-Zn dual-atom cooperative interface sites were fabricated by a Kirkendall effect-pyrolysis strategy. • The shared N between Cu and Zn atoms is rewarding to decrease ORR energy barriers. • The hollow structure of Cu-Zn DA/HNC is beneficial for the exposure of active sites and mass transport. • Cu-Zn DA/HNC presents brilliant ORR performance in an alkaline media. [ABSTRACT FROM AUTHOR]