平衡位移电流技术在中央空调的应用

为解决中央空调在通讯中的噪音问题,本文分析通讯回路和开关电源回路的原理,得到中央空调基板初次级之间的Y电容会形成共模干扰,造成通讯噪音。为去除Y电容,基于开关电源电磁兼容性(electromagnetic compatibility,EMC)技术,采用平衡位移电流技术和双维度黄金分割法,在不改变电路架构的情况下,完成了中央空调基板去Y电容的技术升级迭代,基板上的EMC解决方案由原来的被动滤波变成了主动降噪。

Risk factors and a predictive nomogram for lymph node metastasis in superficial esophageal squamous cell carcinoma

BACKGROUND Superficial esophageal squamous cell carcinoma(ESCC)is defined as cancer infiltrating the mucosa and submucosa,regardless of regional lymph node metastasis(LNM).Endoscopic resection of superficial ESCC is suitable for lesions that have no or low risk of LNM.Patients with a high risk of LNM always need further treatment after endoscopic resection.Therefore,accurately assessing the risk of LNM is critical for additional treatment options.AIM To analyze risk factors for LNM and develop a nomogram to predict LNM risk in superficial ESCC patients.METHODS Clinical and pathological data of superficial ESCC patients undergoing esophagectomy from January 1,2009 to January 31,2016 were collected.Logistic regression analysis was used to predict LNM risk factors,and a nomogram was developed based on risk factors derived from multivariate logistic regression analysis.The receiver operating characteristic(ROC)curve was used to obtain the accuracy of the nomogram model.RESULTSA total of 4660 patients with esophageal cancer underwent esophagectomy.Of these,474 superficial ESCC patientswere enrolled in the final analysis,with 322 patients in the training set and 142 patients in the validation set.Theprevalence of LNM was 3.29%(5/152)for intramucosal cancer and increased to 26.40%(85/322)for submucosalcancer.Multivariate logistic analysis showed that tumor size,invasive depth,tumor differentiation,infiltrativegrowth pattern,tumor budding,and lymphovascular invasion were significantly correlated with LNM.Anomogram using these six variables showed good discrimination with an area under the ROC curve of 0.789(95%CI:0.737-0.841)in the training set and 0.827(95%CI:0.755-0.899)in the validation set.CONCLUSIONWe developed a useful nomogram model to predict LNM risk for superficial ESCC patients which will facilitateadditional decision-making in treating patients who undergo endoscopic resection.

Early esophagus cancer segmentation from gastrointestinal endoscopic images based on U-Net++model

Automatic segmentation of early esophagus cancer(EEC)in gastrointestinal endoscopy(GIE)images is a critical and challenging task in clinical settings,which relies primarily on labor-intensive and time-consuming routines.EEC has often been diagnosed at the late stage since early signs of cancer are not obvious,resulting in low survival rates.This work proposes a deep learning approach based on the U-Net++method to segment EEC in GIE images.A total of 2690 GIE images collected from 617 patients at the Digestive Endoscopy Center,West China Hospital of Sichuan University,China,have been utilized.The experimental result shows that our proposed method achieved promising results.Furthermore,the comparison has been made between the proposed and other U-Net-related methods using the same dataset.The mean and standard deviation(SD)of the dice similarity coefficient(DSC),intersection over union(IoU),precision(Pre),and recall(Rec)achieved by the proposed framework were DSC(%)=94.62±0.02,IoU(%)=90.99±0.04,Pre(%)=94.61±0.04,and Rec(%)=95.00±0.02,respectively,outperforming the others.The proposed method has the potential to be applied in EEC automatic diagnoses.

股四头肌等速肌力训练联合关节腔注射治疗类风湿关节炎缓解期膝关节炎34例临床观察

目的:观察股四头肌等速肌力训练联合关节腔注射治疗类风湿关节炎缓解期膝关节炎的临床疗效。方法:将68例类风湿关节炎缓解期膝关节炎患者按照数字双盲法分为治疗组和对照组,每组34例。对照组给予常规药物加关节腔注射治疗,治疗组给予常规药物加股四头肌等速肌力训练及关节腔注射治疗。观察2组治疗前后膝关节疼痛视觉模拟评分法(VAS)评分、Lysholm膝关节功能评分(Lysholm评分)、股四头肌等速肌力,以及睁闭眼静态平衡功能。结果:治疗后,2组VAS评分较治疗前均有改善(P<0.05);但2组间比较,差异无统计学意义(P>0.05)。治疗2周,2组Lysholm评分较治疗前均有明显改善(P<0.05);但2组间比较,差异无统计学意义(P>0.05)。治疗4周,治疗组Lysholm评分较治疗前有改善(P<0.05);2组间比较,差异有统计学意义(P<0.05)。治疗后,治疗组股四头肌肌力较治疗前有改善(P<0.01);2组间比较,差异有统计学意义(P<0.01)。治疗后,2组睁闭眼静态平衡能力较治疗前均有改善(P<0.05);2组间比较,差异有统计学意义(P<0.05)。结论:股四头肌等速肌力训练、关节腔内注射治疗类风湿关节炎缓解期膝关节炎患者具有协同疗效,股四头肌肌力训练不会加重关节疼痛、增加关节负担,反而能进一步提高患者膝关节稳定性,改善膝关节功能,从而恢复患者日常生活活动能力,值得临床推广。

Efficacy and safety of endoscopic submucosal tunnel dissection for superficial esophageal squamous cell carcinoma and precancerous lesions

AIM To evaluate the clinical outcomes of patients who underwent endoscopic submucosal tunnel dissection(ESTD) for esophageal squamous cell carcinoma(ESCC) and precancerous lesions.METHODS ESTD was performed in 289 patients. The clinical outcomes of the patients and pathological features of the lesions were retrospectively reviewed.RESULTS A total of 311 lesions were included in the analysis. The en bloc rate, complete resection rate, and curative resection rate were 99.04%, 81.28%, and 78.46%, respectively. The ESTD procedure time was 102.4 ± 35.1 min, the mean hospitalization time was 10.3 ± 2.8 d, and the average expenditure was 3766.5 ± 846.5 dollars. The intraoperative bleeding rate was 6.43%, the postoperative bleeding rate was 1.61%, the perforation rate was 1.93%, and the postoperative infection rate was 9.65%. Esophageal stricture and positive margin were severe adverse events, with an incidence rate of 14.79% and 15.76%, respectively. No tumor recurrence occurred during the follow-up period. CONCLUSION ESTD for ESCC and precancerous lesions is feasible and relatively safe, but for large mucosal lesions, the rate of esophageal stricture and positive margin is high.

Risk factors for Mallory-Weiss Tear during endoscopic submucosal dissection of superficial esophageal neoplasms

BACKGROUND Adverse events during endoscopic submucosal dissection(ESD)of superficial esophageal neoplasms,such as perforation and bleeding,have been welldocumented.However,the Mallory-Weiss Tear(MWT)during esophageal ESD remains under investigation.AIM To investigate the incidence and risk factors of the MWT during esophageal ESD.METHODS From June 2014 to July 2017,patients with superficial esophageal neoplasms who received ESD in our institution were retrospectively analyzed.The clinicopathological characteristics of the patients were collected.Patients were divided into an MWT group and non-MWT group based on whether MWT occurred during ESD.The incidence of MWTs was determined,and the risk factors for MWT were then further explored.RESULTS A total of 337 patients with 373 lesions treated by ESD were analyzed.Twenty patients developed MWTs during ESD(5.4%).Multivariate analysis identified that female sex(OR=5.36,95%CI:1.47-19.50,P=0.011)and procedure time longer than 88.5 min(OR=3.953,95%CI:1.497-10.417,P=0.005)were independent risk factors for an MWT during ESD.The cutoff value of the procedure time for an MWT was 88.5 min(sensitivity,65.0%;specificity,70.8%).Seven of the MWT patients received endoscopic hemostasis.All patients recovered satisfactorily without surgery for the laceration.CONCLUSION The incidence of MWTs during esophageal ESD was much higher than expected.Although most cases have a benign course,fatal conditions may occur.We recommend inspection of the stomach during and after the ESD procedure for timely management in cases of bleeding MWTs or even perforation outside of the procedure region.

When and why a colonoscopist should discontinue colonoscopy by himself?

AIM: To investigate when and why a colonoscopist should discontinue incomplete colonoscopy by himself.METHODS: In this cross-sectional study, 517 difficult colonoscope insertions(Grade C, Kudo's difficulty classification) screened from 37800 colonoscopy insertions were collected from April 2004 to June 2014 by three 4th-level(Kudo's classification) colonoscopists. The following common factors for the incomplete insertion were excluded: structural obstruction of the colon or rectum, insufficient colon cleansing, discontinuation due to patient's discomfort or pain, severe colon disease with a perforation risk(e.g., severe ischemic colonopathy). All the excluded patients were re-scheduled if permission was obtained from the patients whose intubation had failed. If the repeat intubations were still a failure because of the difficult operative techniques, those patients were also included in this study. The patient's age, sex, anesthesia and colonoscope type were recorded before colonoscopy. During the colonoscopic examination, the influencing factors of fixation, tortuosity, laxity and redundancy of the colon were assessed, and the insertion time(> 10 min or ≤ 10 min) were registered. The insertion time was analyzed by t-test, and other factors were analyzed by univariate and multivariate logistic regression.RESULTS: Three hundred and twenty-two(62.3%) of the 517 insertions were complete in the colonoscope insertion into the ileocecum, but 195(37.7%) failed in the insertion. Fixation, tortuosity, laxity or redundancy occurred during the colonoscopic examination. Multivariate logistic regression analysis revealed that fixation(OR = 0.06, 95%CI: 0.03-0.16, P < 0.001) and tortuosity(OR = 0.04, 95%CI: 0.02-0.08, P < 0.001) were significantly related to the insertion into the ileocecum in the left hemicolon; multivariate logistic regression analysis also revealed that fixation(OR = 0.16, 95%CI: 0.06-0.39, P < 0.001), tortuosity(OR0.23, 95%CI: 0.13-0.43, P < 0.001), redundancy(OR = 0.12, 95%CI: 0.05-0.26, P < 0.001) and sex(OR = 0.35, 95%CI: 0.20-0.63, P < 0.001) were significantly related to the insertion into the ileocecum in the right hemicolon. Prolonged insertion time(> 10 min) was an unfavorable factor for the insertion into the ileocecum.CONCLUSION: Colonoscopy should be discontinued if freedom of the colonoscope body's insertion and rotation is completely lost, and the insertion time is prolonged over 30 min.

脑出血并迟发性脾破裂一例并文献复习

迟发性脾破裂是脾脏受伤后脾被膜下出现血肿,或脾被膜下的裂口不大,出血缓慢,血液凝固或大网膜包裹裂口而暂时不出血,某种诱因下才出现腹腔内出血症状。生理状态的脾质地软而脆,易受暴击而破裂出血,病理性状态下的脾脏因肿大和脆性增加,更易破裂。其临床表现不典型,症状隐匿,诊断较为困难,误诊率高,使治疗延误。本文对脑出血并迟发性脾破裂病例进行分析,了解脾破裂的病因、发病机制及目前诊断方法,从而更好地服务临床。

Synergism of Pt nanoparticles and iron oxide support for chemoselective hydrogenation of nitroarenes under mild conditions

An efficient and low-cost supported Pt catalyst for hydrogenation of niroarenes was prepared with colloid Pt precursors andα-Fe2O3 as a support.The catalyst with Pt content as low as 0.2 wt%exhibits high activities,chemoselectivities and stability in the hydrogenation of nitrobenzene and a variety of niroarenes.The conversion of nitrobenzene can reach 3170 molconv h^–1 molPt^–1 under mild conditions(30°C,5 bar),which is much higher than that of commercial Pt/C catalyst and many reported catalysts under similar reaction conditions.The spatial separation of the active sites for H2 dissociation and hydrogenation should be responsible for the high chemoselectivity,which decreases the contact possibility between the reducible groups of nitroarenes and Pt nanoparticles.The unique surface properties ofα-Fe2O3 play an important role in the reaction process.It provides active sites for hydrogen spillover and reactant adsorption,and ultimately completes the hydrogenation of the nitro group on the catalyst surface.

Endoscopic submucosal tunnel dissection for early esophageal squamous cell carcinoma in patients with cirrhosis:A propensity score analysis

BACKGROUND Although early esophageal squamous cell carcinoma(EESCC)with cirrhosis is a relatively rare clinical phenomenon,the management of EESCC in cirrhotic patients continues to be a challenge.AIM To evaluate the feasibility,safety,efficacy and long-term survival outcomes of endoscopic submucosal tunnel dissection(ESTD)for treating EESCC in patients with cirrhosis.METHODS This was a single-center retrospective cohort study.We examined 590 EESCC patients who underwent ESTD between July 14,2014,and May 26,2021,from a large-scale tertiary hospital.After excluding 25 patients with unclear lesion areas or pathological results,the remaining 565 patients were matched at a ratio of 1:3 by using propensity score matching.A total of 25 EESCC patients with comorbid liver cirrhosis and 75 matched EESCC patients were ultimately included in the analysis.Parametric and nonparametric statistical methods were used to compare the differences between the two groups.The Kaplan–Meier method was used to create survival curves,and differences in survival curves were compared by the log-rank test.RESULTS Among 25 patients with liver cirrhosis and 75 matched noncirrhotic patients,there were no significant differences in intraoperative bleeding(P=0.234),30-d post-ESTD bleeding(P=0.099),disease-specific survival(P=0.075),or recurrence-free survival(P=0.8196).The mean hospitalization time and costs were significantly longer(P=0.007)and higher(P=0.023)in the cirrhosis group than in the noncirrhosis group.The overall survival rate was significantly lower in the cirrhosis group(P=0.001).CONCLUSION ESTD is technically feasible,safe,and effective for patients with EESCC and liver cirrhosis.EESCC patients with Child-Pugh A disease seem to be good candidates for ESTD.

基于CiteSpace可视化工具对成人体外膜氧合技术领域研究的分析

目的:对2000年至2020年Web of Science收录的成人体外膜氧合(ECMO)相关研究文献进行可视化分析,以解析和追踪成人ECMO技术领域相关热点和前沿。方法:检索2000至2020年在Web of Science核心合集数据库收录的成人ECMO相关研究文献,运用CiteSpace可视化工具,从高影响力国家/地区、机构、作者、高频关键词及突变术语等方面解析成人ECMO技术研究的热点与前沿。结果:最终纳入2058篇以成人ECMO为主题的文献,相关文献年发表量呈现增长趋势,美国发文量位居首位。该领域研究多热点集中在COVID-19、抗凝作用、临床试验。同时,院内心脏骤停、指南、急性呼吸衰竭是成人ECMO研究的前沿领域,代表未来研究发展趋势。结论:临床试验、体外心肺复苏、急性呼吸衰竭、冠状病毒感染方面的研究是成人ECMO技术研究的前沿和热点。

HBS通讯回路硬件电路仿真分析

针对家庭总线系统(home bus system,HBS)通讯回路采用黑盒测试其可靠性存在测评工作量大的问题,本文主要对HBS通讯回路硬件电路进行仿真分析。通过对HBS通讯回路的技术研究,利用专业的仿真软件Stspice,建立HBS通讯回路3个核心仿真模型,提出一种新的白盒测试方式。测试结果表明,采用白盒测试方法,将HBS通讯回路的评测工作量缩减50%,其测试方法远优于现有的黑盒测试方式,而且该方法能够有效定位硬件电路的故障区域,解决了HBS通讯回路在不同商用空调基板上应用的适应性问题。该研究对多联机中央空调HBS回路的可靠性评价具有一定的指导意义。

A feasibility trial of computer-aided diagnosis for enteric lesions in capsule endoscopy

AIM: To investigate and evaluate the feasibility of the computer-aided screening diagnosis for enteric lesions in the capsule endoscopy (CE).METHODS: After developing a series of algorithms for the screening diagnosis of the enteric lesions in CE based on their characteristic colors and contours, the normal and abnormal images obtained from 289 patients were respectively scanned and diagnosed by the CE readers and by the computer-aided screening for the enteric lesions with the image-processed software (IPS). The enteric lesions shown by the images included esoenteritis, mucosal ulcer and erosion, bleeding, space-occupying lesions, angioectasia, diverticula, parasites, etc. The images for the lesions or the suspected lesions confirmed by the CE readers and the computers were collected, and the effectiveness rate of the screening and the number of the scanned images were evaluated, respectively.RESULTS: Compared with the diagnostic results obtained by the CE readers, the total effectiveness rate (sensitivity) in the screening of the commonly-encountered enteric lesions by IPS varied from 42.9% to 91.2%, with a median of 74.2%, though the specificity and the accuracy rates were still low, and theimages for the rarely-encountered lesions were difficult to differentiate from the normal images. However, the number of the images screened by IPS was 5000 on average, and only 10%-15% of the original images were left behind. As a result, a large number of normal images were excluded, and the reading time decreased from 5 h to 1 h on average.CONCLUSION: Though the total accuracy and specificity rates by the computer-aided screening for the enteric lesions with IPS are much lower than those by the CE readers, the computer-aided screening diagnosis can exclude a large number of the normal images and confine the enteric lesions to 5000 images on average, which can reduce the workload of the readers in the scanning of the images. This computer-aided screening technique can make a correct diagnosis as efficiently as possible in most of the patients.

开关电源在中央空调上的归一化设计

为了解决中央空调上开关电源芯片的“缺芯”问题,本文采用优选法,对开关电源拓扑技术进行研究。通过对开关电源进行归一化分析,实现开关电源芯片在中央空调上的归一化设计,使空调基板上的开关电源方案只采用一个芯片。同时,采用Buck实现Flyback功能的架构设计。研究结果表明,采用归一化设计,中央空调上的开关电源芯片由原来的6个变更为1个,最大程度的解决了芯片卡脖子问题。该研究对开关电源回路的通用化、标准化及可靠性设计具有一定的指导意义。

Atomically dispersed materials:Ideal catalysts in atomic era

Catalysts can accelerate the chemical reaction rate and effectively promote the molecules transformation,which is of great significance in the research of chemical industry and material science.The extreme utilization of reactive sites has led to the emergence and development of atomically dispersed materials(ADMs).The highly active coordination unsaturated metal sites and fully utilized metal atoms make ADMs show great potential in catalytic reactions.The adjustment of coordination environment and electronic structure provides more possibilities for constructing reactive centers with different properties.This review summarized the application and research progress of ADMs in different fields.The design strategy and structure–activity relationship of ADMs for specific reactions were summarized and analyzed.Moreover,we also provided advices for the challenges and opportunities faced by ADMs in catalytic reactions.

Construction of spontaneously polarized ceramic via synergistic mechanical activation-Biomimetic mineralization for activating air and water

Spontaneously polarized crystals with intrinsic electric dipole moment have attracted immense interest as excellent functional materials for extensive applications.It is of great significance to engineer sustainable spontaneously polarized materials with fascinating characteristics and performance for activating air and water.Herein,a novel strategy based on the synergy of mechanical activation(MA)and biomimetic mineralization(BM)was created to construct spontaneously polarized ceramic.MA induced the structural damage of clay and promoted the dissolution of ions and the release of free proteins,contributing to the formation of silicate precursor in BM process.After high temperature firing,the silicate precursor in clay was converted to form KCa_(3)AlCa_(3)Si_(4)O_(16)(hexagonal crystal system,L^(6)symmetry type,and P63 space group)in the resulting spontaneously polarized ceramic.The non-centrosymmetric structure of KCa_(3)AlCa_(3)Si4O_(16)and the high intrinsic electric dipole moments contributed by K(1)polyhedrons resulted in high spontaneous polarization(0.2322μC/cm^(2))and far-infrared emissivity(0.951)of spontaneously polarized ceramic.In air,spontaneously polarized ceramic can activate H_(2)O and O_(2)molecules to form negative air ions owing to surface electric field.In water,spontaneously polarized ceramic can disaggregate large water clusters to form small water clusters ascribed to surface electric field and far-infrared emission;water pH can be regulated from weak acidity to approximate neutrality via the capture of electrons by H+ions to produce releasable hydrogen gas.This work provides great promise for rational design and synthesis of spontaneously polarized materials for functional applications.

Pit-Crew心肺复苏模式对胸外按压质量效果的影响

目的观察以Pit-Crew心肺复苏(cardiopulmonary resuscitation, CPR)模式的团队复苏对胸外按压质量改善的效果。方法采用对照研究的方法, 将64名重症医学科和急诊科医护人员按照医护比例分成角色分工组与未角色分工组, 每组各8队, 每队4人。角色分工组每队指定一名队长组织协调整个CPR流程, 未角色分工组不进行指定。每队利用高级模拟人在CPR质量跟踪反馈系统的监测下, 按照《2020年美国心脏协会心肺复苏和心血管急救指南》推荐要求实施标准胸外心脏按压8 min。观察并记录每队实验人员CPR时间、胸外按压比例(chest compression fraction, CCF)、按压中断次数、按压超标中断次数(>10 s)、按压频率、胸廓充分回弹次数等指标。电脑系统记录以上参数, 两组间指标的差异比较采用独立样本t检验和Mann-Whitney U检验。结果分析发现, 与未角色分工组相比, 角色分工组能达到更高CCF[(69.13±1.55)%vs. (59.13±6.08)%, P<0.05], 且角色分工组的按压中断总时间及超标中断次数均显著较少[(79.88±28.76)svs. (135.25±32.99)s;4(3, 5)次vs. 2(1, 2)次, 均P<0.01]。两组在CPR时间、中断次数及按压总时间方面的均差异无统计意义(均P>0.05), 另外两组在按压总次数、按压正确次数、按压频率、按压深度、胸廓充分回弹等按压质量达标方面以及在按压太快、按压太慢、按压太深以及胸廓回弹不足等按压质量未达标方面均差异无统计学意义(均P>0.05)。结论以指定团队领导的Pit-Crew CPR模式有助于实施高质量的CPR, 而且CPR质量参数的监测与实施实时反馈系统能有效提高胸外按压的质量。

2000年至2020年脓毒症心肌病领域的研究进展:基于知识可视化分析

目的基于知识可视化分析,探讨2000年至2020年脓毒症心肌病(SCM)领域的研究进展。方法收集2000年1月1日至2020年12月20日中国知网(CNKI)及科学网(WOS)数据库收录的SCM研究领域相关文献。应用Excel软件对数据进行整理并绘制文献增长柱状图;应用CiteSpace 5.0 R1软件对国家、研究机构、作者信息进行提取及整理并生成相关共现网络,分析该领域主要研究力量分布及合作关系,对关键词及相关引文进行分析并绘制共被引文献网络,分析该领域前沿及热点信息。结果共收集中文文献774篇,英文文献1883篇,中文文献只进行研究机构、发文量、作者的统计描述,所有英文文献均纳入可视化分析。在发文量方面,2000年至2020年SCM研究领域相关国内外文献数量均呈迅速增长,英文文献数量多于中文文献。英文文献分析显示,全球发文量排名前3位的国家依次为美国(618篇)、中国(441篇)、德国(140篇)。从研究机构上看以武汉大学29篇位列WOS首位,德克萨斯大学与哈佛大学分别位列第2、3位;国内发文最多的研究机构为上海中医药大学(21篇)。作者共现网络分析显示在全球形成了四大科研团体,其中以Horton JW、Neviere R、Li CF和Thiemermann C对该领域贡献最大,其中中国学者在该领域研究势头强劲。关键词共现分析显示,研究热点主要围绕脓毒症患者的心功能及预后方面,而通过突增关键词分析可以看出国内文献更多地关注药物对SCM的治疗效果,而国外文献则更多地倾向对SCM的发病机制与管理方面的研究。共被引文献网络分析显示,未来对SCM的研究也应将从临床-机制-管理这几个方面着手,这也与突增关键词分析结果相吻合。结论通过知识可视化分析可以直观显示,SCM领域主要研究力量大多集中于美国、欧洲等发达国家,但中国学者势头强劲。未来研究趋势倾向于SCM的机制及治疗管理方面。

Single Cu atom dispersed on S,N-codoped nanocarbon derived from shrimp shells for highly-efficient oxygen reduction reaction

Recently,Cu-based single-atom catalysts(SACs)have garnered increasing attention as substitutes for platinum-based catalysts in the oxygen reduction reaction(ORR).Therefore,a facile,economical,and efficient synthetic methodology for the preparation of a high-performance Cu-based SAC electrocatalyst for the ORR is extremely desired,but is also significantly challenging.In this study,we propose a ball-milling method to synthesize isolated metal SACs embedded in S,N-codoped nanocarbon(MNSDC,M=Cu,Fe,Co,Ni,Mn,Pt,and Pd).In particular,the Cu-NSDC SACs exhibit high electrochemical activity for the ORR with half-wave potential(E_(1/2))of 0.84 V(vs.reversible hydrogen electrode(RHE),20 mV higher than Pt/C)in alkaline electrolyte,excellent stability,and electrocatalytic selectivity.Density functional theory(DFT)calculations demonstrated that the desorption of OH*intermediates was the rate-determining step over Cu-NSDC.This study creates a pathway for high-performance ORR single atomic electrocatalysts for fuel cell applications and provides opportunities to convert biowaste materials into commercial opportunities.

Quasi-continuous synthesis of cobalt single atom catalysts for transfer hydrogenation of quinoline

Improving the transfer hydrogenation of N-heteroarenes is of key importance for various industrial pro-cesses and remains a challenge so far.We reported here a microcapsule-pyrolysis strategy to quasi-continuous synthesis S,N co-doped carbon supported Co single atom catalysts(Co/SNC),which was used for transfer hydrogenation of quinoline with formic acid as the hydrogen donor.Given the unique ge-ometric and electronic properties of the Co single atoms,the excellent catalytic activity,selectivity and stability were observed.Benefiting from the quasi-continuous synthesis method,the as-obtained cata-lysts provide a reference for the large-scale preparation of single atom catalysts without amplification ef-fect.Highly catalytic performances and quasi-continuous preparation process,demonstrating a new and promising approach to rational design of atomically dispersed catalysts with maximum atomic efficiency in industrial.