Heterostructured Pt-Ni_(3)Mo_(3)N formed via ammonia-containing polyoxometalates for highly efficient electrocatalytic hydrogen evolution in acid medium

Constructing heterostructured nanohybrid is considered as a prominent route to fabricate alternative electrocatalysts to commercial Pt/C for hydrogen evolution reaction(HER).In this work,(NH_(4))_(4)[NiH_(6)Mo_(6)O_(4)]·5H_(2)O polyoxometalates(NiMo_(6))are adopted as the cluster precursors for simple fabrication of heterostructured Pt-Ni_(3)Mo_(3)N nanohybrids supported by carbon black(Pt-Ni_(3)Mo_(3)N/C)without using additional N sources.The improved porosity and enhanced electronic interaction of Pt-Ni_(3)Mo_(3)N/C should be attributed to the integration of Pt with NiMo_(6),which favors the mass transport,promotes the formation of exposed catalytic sites,and benefits the regulation of intrinsic activity.Thus,the as-obtained Pt-Ni_(3)Mo_(3)N/C exhibits impressive and durable HER performance as indicated by the low overpotential of 13.7 mV at the current density of 10 mA cm^(-2) and the stable overpotential during continuous working at 100 mA cm^(-2) for 100 h.This work provides significant insights for the synthesis of new highly active heterostructured electrocatalysts for renewable energy devices.

Molecule aging induced by electron attacking

Here we propose a new concept of"molecule aging":with some special treatment,a molecule could be"aged"by losing some unknown tiny particles or pieces from atoms in the molecule,Such"aging"or loss of unknown tiny particles does not change apparently its molecular structure or chemical composition,but some physicochemical properties could be changed irreversibly.We further confirm such"molecule aging"via a long-term electron attacking to age water(H_(2)O)molecules.The IR spectra show no structural difference between the fresh water and the aged one,while the NMR spectra show that the electron attacking can decrease the size of water clusters.Such facts indicate that the electron attacking indeed can"affect"the structure of water molecule slightly but without damaging to its basic molecule frame.Further exploration reveals that the hydrogen evolution reaction(HER)activity of the aged water molecule is lower than the fresh water on the same Pt/C electrocatalyst.The density functional theory calculations indicate that the shortened O-H bond in H_(2)O indeed can present lower HER activity,so the observed size decrease of water clusters from NMR probably could be attributed to the shortening of O-H bond in water molecules.Such results indicate significantly that the molecule aging can produce materials with new functions for new possible applications.

A Preliminary Study on Consumer Sensory Evaluation and Acceptance of Pomelo Peel Jelly

Pomelo peel is a by-product from pomelo consumption, but it is also rich in a variety of nutrients and functional substances. In order to solve the environmental problems caused by the large amount of discarded pomelo peels every year, in this study, we recycled pomelo peels to make pomelo yellow peel jelly (PYPJ) and pomelo white peel jelly (PWPJ) according to their different characteristics in pomelo peels. And the consumer sensory evaluation (n = 50) was carried out to explore the consumers’ evaluation and acceptance for these two innovative products. The results showed that both jellies received high mean scores for all sensory attributes expect PYPJ’ taste, and the consumer acceptances of PYPJ and PWPJ were 62% and 92%, respectively. These results displayed that there is a need to further improve PYPJ, and PWPJ is a product recognized by consumers. .

钒掺杂钨青铜内通道氨配位的钌单原子用于高效析氢反应

通过电解水制备氢气是实现“碳中和”目标的理想途径之一.因此,可在全p H条件下使用的氢析出(HER)催化剂的研发是近年来电催化领域的研究热点.原子级分散的催化剂,能够在保留铂族金属(PGM)固有活性的同时,降低催化剂中PGM的用量.虽然可以通过X射线吸收光谱(XAS)来表征原子分散的PGM电催化剂的配位环境,但目前对原子空间分布的控制仍然具有挑战.本文制备了钒掺杂钨青铜内通道氨配位的钌单原子催化剂(Ru/V-NHWO),用于全p H范围内的HER反应.采用X射线衍射(XRD)、高角环形暗场扫描透射电镜(HAADF-STEM)、X射线光电子能谱(XPS)和原位X射线吸收光谱(XAS)等进行表征,研究了钌单原子与V-NHWO载体的结合方式以及构效关系,并采用密度泛函理论(DFT)计算探索了催化剂中诸多位点的活性贡献.在1 mol/LKOH, 0.5 mol/L H_(2)SO_(4)和1 mol/L磷酸盐缓冲溶液中,其在10 m Acm^(-2)下的过电位分别为28.0, 29.6和40.6 m V.同时,在过电位100 m V时,质量活性分别达到3930, 1941和602.8 m Amg^(-1)Ru,数倍于同等条件下的商业铂碳.XRD结果表明,钌的引入可以确保催化剂在氩气条件下热解后仍保持六方钨铵青铜晶相,证明钌与钨铵青铜六方晶体通道内氨物种,即“通道氨”的结合.HAADF-STEM结果表明,钌原子与NHWO间存在强烈相互作用,有助于提升HER性能.XPS和XAS结果表明, W5+信号出现在引入钌后,峰位置的结合能增加且峰面积降低,说明钌与通道氨之间存在相互作用.N的XPS结果表明,钌的引入导致了金属氨键的形成.XAS结果表明, Ru/V-NHWO/CC中钌单原子和钌团簇共存,钌单原子与通道氨配位,并且钒的引入会诱发V-NHWO中金属键长缩短,这表明催化剂的金属性得到了提升,有利于改善其导电性.采用DFT计算进一步研究了HER活性的来源.相比于V-NHWO载体和钌团簇修饰的V-NHWO,以单原子形式结合的钌具有更低的水解离能垒,该能垒在氨桥接的钌双原子垂直插入、钒掺杂和多通道插入等多种因素作用下进一步降低.同时,氢中间体结合能得到了相应的优化而趋近于0 e V.此外,差分电荷密度模拟结果表明,氢中间体结合后, V-NHWO对于钌单原子存在明显的供电子行为,有利于HER动力学过程.综上,本工作报道了金属载体对于高分散金属原子空间分布调控的重要作用,可为设计和构筑可应用于诸多能源转换过程的新型原子级分散催化剂提供参考.

非Pt基催化剂在质子交换膜燃料电池阴极氧还原反应中的研究进展

对绿色、高效能源储存装置日趋强烈的需求,使得用于清洁能源转换的先进技术获得了研究者的密切关注。具有环境友好、高能量转换效率等优势的燃料电池是传统能源转换装置极具希望的替代品。然而,工业催化界中商业化程度高的Pt体系催化剂存在成本高、稳定性差和抗毒化能力弱等问题,限制了燃料电池的进一步发展。开发储量丰富、成本低廉且性能优异的非Pt体系氧还原(ORR)催化剂是降低燃料电池成本,促进其大规模应用的有效途径。对此,结合近10年来国内外研究成果,系统介绍了当前各类非Pt体系ORR催化剂的研究进展,包括非贵金属基以及非金属基催化剂。同时,针对各类催化剂的优点、不足及改性策略进行了归纳与总结,并对未来ORR电催化剂的发展提出挑战、做出展望。

Piggyback人工晶状体植入术临床应用进展

随着现代手术设备、人工晶状体种类的不断进步与发展以及人们对视觉质量要求的不断提高,白内障手术已经从传统复明手术转化为一种高质量、高需求的屈光性手术。Piggyback人工晶状体植入术起初是临床医生为了Ⅰ期矫正高度远视或者Ⅱ期矫正白内障术后存在屈光误差,在患者眼内植入2枚或2枚以上的后房型人工晶状体,以达到矫正屈光不正目的的一种新型手术方式。近年来,随着功能性晶状体的诞生和推广,该技术被应用于屈光性白内障领域,扩大了功能性人工晶状体的应用范围,并且达到了良好的术后效果。本综述讨论了Piggyback人工晶状体植入术的发展历程以及目前在临床上的应用情况,并进一步阐明了该技术未来的发展趋势。

Tuning strategies and structure effects of electrocatalysts for carbon dioxide reduction reaction

Carbon dioxide emissions have increased due to the consumption of fossil fuels,making the neutralization and utilization of CO_(2) a pressing issue.As a clean and efficient energy conversion process,electrocatalytic reduction can reduce carbon dioxide into a series of alcohols and acidic organic molecules,which can effectively realize the utilization and transformation of carbon dioxide.This review focuses on the tuning strategies and structure effects of catalysts for the electrocatalytic CO_(2) reduction reaction(CO_(2)RR).The tuning strategies for the active sites of catalysts have been reviewed from intrinsic and external perspectives.The structure effects for the CO_(2)RR catalysts have also been discussed,such as tandem catalysis,synergistic effects and confinement catalysis.We expect that this review about tuning strategies and structure effects can provide guidance for designing highly efficient CO_(2)RR electrocatalysts.

Evaluation of umami taste components of mushroom (Suillus granulatus) of different grades prepared by different drying methods

Suillus granulatus is a valuable wild edible mushroom with a strong umami taste.Different grades of S.granulatus were dried by different methods,including natural air drying(ND),hot air drying(HAD),vacuum drying(VD),and freeze drying(FD).Results showed that VD samples of all grades had the highest equivalent umami concentration(EUC)value(P<0.05).The second grade of ND samples showed the highest EUC value(P<0.05).The first grade of HAD samples showed the highest EUC value(P<0.05).The third grade of FD samples showed the highest EUC value(P<0.05).The third grade of VD samples had a higher EUC value than the other grades of samples dried by VD.Electronic tongue results indicated no significant differences between samples of all grades dried by all methods.Thus,umami taste components are affected by drying method and grade.VD is an appropriate drying method for all sample grades.ND,HAD,and FD are suitable for second-,first-,and third-grade samples,respectively.

Construction of the First Certification Evaluation Index System for Diabetes Specialist Nurses by Delphi Method

Objective: To establish an evaluation index system for the first-time certification of diabetes specialist nurses in line with the clinical nursing practice in China, and to provide a reference basis for government administrations and hospitals to formulate unified standards. Methods: After the research team has determined the theme, it will consult the development of A) specialist nursing through the library, Internet and electronic literature database;B) the history of the development of specialist nurses in diabetes and other fields;C) the selection criteria of specialist nurses;D) the training of specialist nurses system, assessment method;E) Specialist nurse certification body, evaluation standards and certification standards and other related documents, literature, books and report materials. The author established the preliminary index system through literature review, specialist interview and group discussion and used Delphi method to organize three rounds of 30 experts’ consultations. Results: A first certification evaluation index system including 8 fundamental indicators, 5 first-level indicators, 19 second-level indicators and 99 third-level indicators was constructed for diabetes nurses. Conclusion: The results of three rounds of expert consultation and demonstration are reliable, and the constructed index system is suitable for comprehensive evaluation of diabetes specialist nurses, which provides a basis for the effective management of nursing resources.

Poly(ether ether ketone ketone) based imidazolium as anion exchange membranes for alkaline fuel cells

An imidazolium functionalized poly(ether ether ketone ketone)(PEEKK-DIm OH)anion exchange membrane(AEM)readily soluble in certain low-boiling-point solvents(isopropanol)is prepared.The solubility results are consistent with the results of molecular dynamics simulations.By varying the chloromethylation reaction temperature or concentrated sulfuric acid concentration of PEEKK,the degrees of chloromethylation of PEEKK are changed from 54% to 92%,the corresponding PEEKK-DIm OH AEMs with the ion exchange capacities(IECs)of 1.14–1.65 mmol·g^(-1).The PEEKK-DIm OH 92% AEM shows high hydroxide conductivity(31 m S·cm^(-1)),suitable water uptake(94%)and acceptable swelling ratio(39%)at 60°C.In addition,the PEEKK-DIm OH AEMs possess good thermal and alkaline stability.The maximum power density(46.16 mW·cm^(-2))of fuel cell prepared with PEEKK-DIm OH 92%AEM as exchange membrane and ionomer is much higher than that with commercial AHA membranes.All the above results indicate that the PEEKK used in this study is a promising AEM matrix material for alkaline fuel cells.

Local parameter identification with neural ordinary differential equations

The data-driven methods extract the feature information from data to build system models, which enable estimation and identification of the systems and can be utilized for prognosis and health management(PHM). However, most data-driven models are still black-box models that cannot be interpreted. In this study, we use the neural ordinary differential equations(ODEs), especially the inherent computational relationships of a system added to the loss function calculation, to approximate the governing equations. In addition, a new strategy for identifying the local parameters of the system is investigated, which can be utilized for system parameter identification and damage detection. The numerical and experimental examples presented in the paper demonstrate that the strategy has high accuracy and good local parameter identification. Moreover, the proposed method has the advantage of being interpretable. It can directly approximate the underlying governing dynamics and be a worthwhile strategy for system identification and PHM.

Acute mesenteric ischemia secondary to oral contraceptive-induced portomesenteric and splenic vein thrombosis:A case report

BACKGROUND Mesenteric ischemia represents an uncommon complication of splanchnic vein thrombosis,and it is less infrequently seen in young women using oral contraceptives.Diagnosis is often delayed in the emergency room;thus,surgical intervention may be inevitable and the absence of thrombus regression or collateral circulation may lead to further postoperative ischemia and a fatal outcome.CASE SUMMARY We report a 28-year-old female patient on oral contraceptives who presented with acute abdominal pain.Her physical examination findings were not consistent with her symptoms of severe pain and abdominal distention.These findings and her abnormal blood tests raised suspicion of acute mesenteric ischemia(AMI)induced by splanchnic vein thrombosis.Contrast-enhanced abdominal computed tomography revealed ischemia of the small intestine with portomesenteric and splenic vein thrombosis(PMSVT).We treated the case promptly by anticoagulation after diagnosis.We then performed delayed segmental bowel resection after thrombus regression and established collateral circulation guided by collaboration with a multidisciplinary team.The patient had an uneventful postoperative course and was discharged 14 d after surgery and took rivaroxaban orally for 6 mo.In subsequent follow-up to date,the patient has not complained of any other discomfort.CONCLUSION AMI induced by PMSVT should be considered in young women who are taking oral contraceptives and have acute abdominal pain.Prompt anticoagulation followed by surgery is an effective treatment strategy.

Multimodal imaging of the carriers of choroideremia and X-linked retinitis pigmentosa

Dear Editor,We are Dr. Zhi-Qing Li and Dr. Jin Yang, from the Neuro-ophthalmology and Medical Retinal Department of Tianjin Medical University Eye Hospital, Tianjin, China. We here present two cases of X-linked inheritable retinal diseases with genetic confirmation of the multimodal imaging findings of the patients, especially the female carriers. This study was approved by the institutional review board of Tianjin Medical University Eye Hospital, and the protocols adhered to the tenets of the Declaration of Helsinki. This letter mainly describes a novel imaging modality, multispectral imaging （MSI）, which appeared to be sensitive in detecting the pattern of chorioretinal degeneration and the tapetal-like reflex.

Changes in the peripapillary vasculature and macular thickness after cataract surgery using two phacoemulsification systems with optical coherence tomography angiography

AIM:To assess the changes in the peripapillary vasculature and macular thickness after cataract surgery using two phacoemulsification systems with optical coherence tomography angiography(OCTA).METHODS:Fifty-two eyes of 52 patients with agerelated cataract were randomized into two groups for phacoemulsification:Infiniti group(26 patients)using the Infiniti phacoemulsification system with gravity-fluidics and Centurion group(26 patients)using the Centurion phacoemulsification system with active-fluidics.The peripapillary vessel density(PVD)and macular thickness were examined using OCTA at baseline and at 1d,1 and 3mo after cataract surgery.RESULTS:In the Infiniti group,the PVD was significantly reduced at 1d after the cataract surgery(P<0.001).However,the retinal nerve fiber layer(RNFL)thickness showed no significant change during the follow-up.Change in PVD 1d postoperatively was significantly negatively correlated to the cumulative dissipated energy(CDE),estimated fluid usage(EFU),effective phacoemulsification time(EPT),intraocular pressure(IOP),and total operating time(TOT;P<0.05).The macular thickness was significantly increased in all regions after the cataract surgery(P<0.05).However,no significant changes were found in the macular vessel density(VD)during the follow-up(P>0.05).In the Centurion group,the VD and thickness in the optic papilla and macula did not significantly change in all regions during the follow-up(all P>0.05).The best-corrected visual acuity(BCVA)significantly improved in both groups postoperatively(P<0.001).CONCLUSION:Using the Infiniti phacoemulsification system,OCTA provides a promising analysis of retinal vascular alterations,demonstrating a reduction of the PVD and an increase in the macular thickness.The Centurion phacoemulsification system can provide better retinal vasculature preservation during cataract surgery.

Uncertainty index and stock volatility prediction:evidence from international markets

This study investigates the predictability of a fixed uncertainty index(UI)for realized variances(volatility)in the international stock markets from a high-frequency perspective.We construct a composite UI based on the scaled principal component analysis(s-PCA)method and demonstrate that it exhibits significant in-and out-of-sample predictabilities for realized variances in global stock markets.This predictive power is more powerful than those of two commonly employed competing methods,namely,PCA and the partial least squares(PLS)methods.The result is robust in several checks.Further,we explain that s-PCA outperforms other dimension-reduction methods since it can effectively increase the impacts of strong predictors and decrease those of weak factors.The implications of this research are significant for investors who allocate assets globally.

Effect of Xifeng Capsule on blood stasis in patients with rheumatoid arthritis by regulating miR-126-VEGF/PI3K/AKT signaling pathway

Objective:From the perspective of miR-126-vascular endothelial cytokine(VEGF)/phosphatidylinositol 3-kinase(PI3K)/ser-threonine protein kinase(AKT)signaling pathway,Xinfeng Capsule(XFC)can improve rheumatoid arthritis(RA))The mechanism of the patient's blood stasis state.Methods:Sixty RA patients meeting the diagnostic criteria were selected and divided into XFC treatment group 30 cases and Leflunomide(LEF)control group 30 cases according to the random number table method.The treatment group took Xinfeng Capsules(3 capsules each time,3 times/d),and the control group took Leflunomide(1 capsule each time,1 times/d).Observe the blood stasis symptom scores of RA patients,and detect the laboratory indicators erythrocyte sedimentation rate(ESR),c-reactive protein(CRP),rheumatoid factor(RF),anti-cyclic citrullinated peptide antibody(CCP),thrombin time(TT),part prothrombin time(APTT),prothrombin time(PT),D dimer(DD),fibrinogen(FBG),platelets(PLT),mean platelet volume(MPV),platelet distribution width(PDW)levels.Real-time fluorescent quantitative PCR method was used to detect the level of miR-126,and the ELISA method was used to detect the levels of tumor necrosis factor(TNF-α),interleukin-6(IL-6),IL-35,VEGF,PI3K,and AKT.Spearman method was used to analyze the correlation between the total score of blood stasis symptoms,blood stasis-related indicators and disease activity indicators,cytokines,miR-126,VEGF,PI3K,and AKT in RA patients.Results:Comparing the two groups after treatment,the XFC group improved blood stasis symptoms,disease activity indicators,decreased miR-126,VEGF,PI3K,AKT,TNF-α,IL-6,D-D,FBG,PLT,and increased IL-35 The level was significantly better than the LEF group,with statistical significance(P<0.05,P<0.01).Correlation analysis showed that there was a certain correlation between the total score of blood stasis symptoms,blood stasis related indicators and disease activity indicators,cytokines,miR-126,VEGF,PI3K,and AKT in RA patients.Conclusion:There is blood stasis in RA patients.XFC may improve the cytokine network disorder of patients through miR-126-VEGF/PI3K/AKT signaling pathway,thereby improving the blood stasis status of RA patients.

Research on the Method of Calculating Node Injected Reactive Power Based on L Indicator

With the power grid load increasing, the problem of grid voltage stability is increasingly prominent, and the possibility of voltage instability is also growing. In order to improve the voltage stability, this paper analyzed how the voltage stability was influenced by different reactive power injection based on the simplified L-indicator of on-line voltage stability monitoring. According to the basic differential property of the simplified L-indicator, a general and normative analytical algorithm about reactive power optimization was deduced. The analytical algorithm can calculate the load node injected reactive power, and then the network can run in the optimal steady state on the basis of the calculation results. According to the simulation results of IEEE-14, IEEE-30, IEEE-57 and IEEE-118, the feasibility and effectiveness of the proposed algorithm to improve voltage stability and reduce the risk of grid collapse were verified.

Metal−support interaction in single-atom electrocatalysts:A perspective of metal oxide supports

The discovery of single-atom catalysts(SACs)represents a groundbreaking advancement in the field of catalysis over the past decades.With the in-depth exploration of relevant structure-activity relationships,the metal−support interaction(MSI)is widely adopted to elucidate variations in electronic structure and coordination configuration of atomic active sites on various kinds of supports.Herein,we briefly summarize the metal oxide supports for SACs fabrication,including the distinctive characteristics of metal oxide supports,enlightening advancements in metal oxide support-based SACs(MO-SACs),feasible preparation methods for MO-SACs and effective regulation strategies of MSI effect in MO-SACs.In addition,we present our viewpoints and outlook in this field to stimulate rational design and construction of novel MO-SACs applied in diverse renewable energy devices,while some universal suggestions are sincerely given to provoke thoughtful considerations during the research process.

Cross-linked Electrospun Gel Polymer Electrolytes for Lithium-Ion Batteries

Lithium-ion batteries(LIBs)benefit from an effective electrolyte system design in both terms of their safety and energy storage capability.Herein,a series of precursor membranes with high porosity were produced using electrospinning technology by mixing PVDF and triblock copolymer(PS-PEO-PS),resulting in a porous structure with good interconnections,which facilitates the absorbency of a large amount of electrolyte and further increases the ionic conductivity of gel polymer electrolytes(GPEs).It has been demonstrated that post-cross-linking of the precursor membranes increa ses the rigidity of the nanofibers,which allows the polymer film to be dimensionally sta ble up to 260℃while maintaining superior electrochemical properties.The obtained cross-linked GPEs(CGPEs)showed high ionic conductivity up to 4.53×10^(-3)S·cm^(-1).With the CGPE-25,the assembled Li/LiFeP04 half cells exhibited good rate capability and maintained a capacity of 99.4%and a coulombic efficiency of99.3%at 0.1 C.These results suggest that the combination of electrospinning technique and post-cross-linking is an effective method to construct polymer electrolytes with high thermal stability and steadily decent electrochemical performance,particularly useful for Lithium-ion battery applications that require high-temperature usage.

A nested partitioning-based solution method for seru scheduling problem with resource allocation

This paper investigates the production scheduling problems of allocating resources and sequencing jobs in the seru production system(SPS).As a new-type manufacturing mode arising from Japanese production practices,seru production can achieve efficiency,flexibility,and responsiveness simultaneously.The production environment in which a set of jobs must be scheduled over a set of serus according to due date and different execution modes is considered,and a combination optimization model is provided.Motivated by the problem complexity and the characteristics of the proposed seru scheduling model,a nested partitioning method(NPM)is designed as the solution approach.Finally,computational studies are conducted,and the practicability of the proposed seru scheduling model is proven.Moreover,the efficiency of the nested partitioning solution method is demonstrated by the computational results obtained from different scenarios,and the good scalability of the proposed approach is proven via comparative analysis.