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Degradation study on tin- and bismuth-based gas-diffusion electrodes during electrochemical CO_(2) reduction in highly alkaline media

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Journal of Energy Chemistry 2021年第11期30卷 367-376,I0008页

作者： Fabian Bienen Armin Lowe Joachim Hildebrand Sebastian Hertle Dana Schonvogel Dennis Kopljar Norbert Wagner Elias klemm Kaspar Andreas Friedrich Institute of Engineering Thermodynamics German Aerospace CenterPfaffenwaldring 38-4070569 StuttgartGermany Institute of Building Energetics Thermal Engineering and Energy StorageUniversity of StuttgartPfaffenwaldring 3170569 StuttgartGermany Institute of Technical Chemistry University of StuttgartPfaffenwaldring 5570569 StuttgartGermany Institute of Engineering Thermodynamics German Aerospace CenterCarl-von-Ossietzky-Straße 1526129 OldenburgGermany

This work investigated the degradation of tin – based gas-diffusion electrodes (GDE) and also a promising Bi2O3 GDE in electrochemical CO_(2) reduction in highly alkaline media which has not been studied before. The contributions of the electrode wetting (or flooding, if excessively) and catalyst leaching on the degradation were analyzed. Therefore, electrochemical impedance spectroscopy was used to monitor the wetted surface area of the GDE in combination with post-mortem analysis of the penetration depth by visualizing the electrolyte’s cation in the GDE cross-section. Furthermore, to reveal a possible degradation of the electrocatalyst, its distribution was mapped in the GDEs cross-section after operation while the catholyte was additionally analyzed via ICP-MS. The results clearly demonstrate that the SnO_(2) catalyst dissolves in the reaction zone inside the GDE and might be partially redeposited near the GDEs surface. Since the redeposition process occurs only partially a steady loss of catalyst was observed impeding a clear distinction of the two degradation phenomena. Nevertheless, the deterioration of the electrode performance measured as faraday efficiency (FE) of the parasitic hydrogen evolution reaction (HER) qualitatively correlates with the differential double layer capacitance (Cdl). A significant difference of the rate of increase for the hydrogen FE and Cdl can be ascribed to the superposition of both above-mentioned degradation mechanisms. The demonstrated instability of SnO_(2) contrasts with the behavior of Bi2O3 GDE which is stabilized during CO_(2) conversion by redeposition of the diluted dissolved species as metallic Bi which is active for the CO_(2) reduction reaction.

关键词： Electrochemical CO_(2)reduction Heterogeneous catalysis Gas-diffusion electrode Electrochemical impedance spectroscopy Catalyst leaching

Recruitment of Minorities into Nursing, Best Practices: A Scoping Review

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Open Journal of Nursing 2022年第10期12卷 683-701页

作者： Paula R. klemm Hason Jafrey School of Nursing University of Delaware Newark Delaware USA Christiana Care Health System Newark Delaware USA

The recruitment and retention of minorities into nursing is a pressing need given the evolving racial makeup of the U.S. A scoping review of the literature was conducted to identify and map evidence of the best practices and timing for recruitment and retention of minorities in nursing. This review utilized methods described by Asksey and O’Malley. PubMed, CINAHL, SCOPUS, Cochrane, Web of Science, and ProQuest were searched from 2000 to 2022. Data were extracted from 20 full text papers published in English in the U.S. Recruitment usually begins in middle or high school, but several authors recommended beginning as early as elementary school to establish positive views of nursing. Retention methods included multi-pronged approaches tailored by the academic institutions. Most received federal funding. Financial aid is key to the success for many minority nursing students, but must be aligned with other supports (e.g., academic, social, mentoring) in recruitment and retention efforts. Partnerships with local elementary, middle, and high schools, hospitals, community agencies and centers, businesses, and minority groups are necessary. Future research that measures outcomes of early recruitment of minorities and their choice of nursing as a career is needed. Recruitment and retention efforts should include information on potential sources of funding prior to student enrollment. More information is needed on recruitment and retention programs that are successful without funding and those that remain robust after funding ends.

关键词： Recruitment and Retention African American Nursing

Paediatric primary care in Germany during the early COVID-19 pandemic:the calm before the storm

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Family Medicine and Community Health 2021年第2期9卷 40-47页

作者： Malte Kohns Vasconcelos Katharina Weil Daniela Vesterling-Hörner Mehrsad klemm Tarik el Scheich Hanna Renk Katharina Remke Hans Martin Bosse Institute for Medical Microbiology and Hospital Hygiene Heinrich Heine University DüsseldorfDüsseldorfGermany Department for General Paediatrics Neonatology and Paediatric CardiologyUniversity Hospital DüsseldorfDüsseldorfGermany Paediatric Practice Dr.med.Vesterling-Hörner DüsseldorfGermany Kinderärzte im Karree LeverkusenGermany Kinderärzte am Zoo DüsseldorfGermany Department of Paediatric Cardiology Pulmonology and Intensive Care MedicineUniversity Children’s Hospital TübingenTübingenGermany

Objectives Globally,the COVID-19 pandemic has a major impact on healthcare *** effects in primary care are *** study aimed to explore changes in consultation numbers and patient management during the COVID-19 pandemic,and to identify challenges for patient *** Survey of paediatric primary care practices on consultation numbers and patient management changes,and semistructured interviews to identify challenges for patient *** and interviews were partially linked in an explanatory sequential design to identify patient groups perceived to be at higher risk for worse care during the *** In and around Düsseldorf,a densely populated area in Western *** primary care facilities are spread over an area with approximately 2 million *** Primary care in Germany is provided through practices run by self-employed specialist physicians that are contracted to offer services to patients under public health insurance which is compulsory to the majority of the *** sample contained 44 paediatric primary care practices in the area,the response rate was 50%.Results Numbers of consultations for scheduled developmental examinations remained unchanged compared with the previous year while emergency visits were strongly reduced(mean 87.3 less/week in March-May 2020 compared with 2019,median reduction 55.0%).Children dependent on developmental therapy and with chronic health conditions were identified as patient groups receiving deteriorated *** patient numbers,including of mildly symptomatic children presenting for health certificates,in combination with increased organisational demands and expected staff outages are priority concerns for the *** Primary care paediatricians offered stable service through the early pandemic but expected strained resources for the upcoming *** guidance on which children should present to primary care and who should be tested would h

关键词： winter storm unchanged

Mechanical Properties of Remote-Laser Cut CFRP and Thermographic Laser-Process Monitoring

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Materials Sciences and Applications 2020年第8期11卷 560-575页

作者： Michael Rose Sebastian Schettler Florian klemm Eckhard Beyer Martina Zimmermann Technische Universitä t Dresden Institute of Materials Science Dresden Germany Fraunhofer Institute for Material and Beam Technology Dresden Germany Technische Universitä t Dresden Institute of Manufacturing Science and Engineering Dresden Germany

Remote-laser beam cutting is a productive technology without tool wear. Especially when cutting carbon fiber reinforced polymers (CFRP), it offers constant manufacturing quality. Since it is a thermal process, a heat-affected zone (HAZ) is formed at the edge of the cut. Based on quasi-static and cyclic mechanical tests on open-hole specimens, the influence of the process on the mechanical properties of CFRP is shown. The quasi-static tests are in good correlation with results from other researchers by indicating an increase in the maximum tensile stress of the test specimens, cut by remote-laser. The reason is the rearrangement of the shear stresses and a reduction of the notch stress concentration. However, the results of the present study show that excessive expansion of the HAZ leads to a reduction in the maximum tensile stress compared to milled test specimens. Under cyclic load conditions, remote-laser beam cutting does not lead to a more pronounced degradation than milling. The mechanical properties of the notched test pieces are sensitive to the expansion of the HAZ. For the production of components it is therefore necessary that the remote-laser beam cutting is carried out under controlled and documentable conditions. For this purpose, process thermography was tested as a tool for quality assurance. The results show that the technology is basically suitable for this task.

关键词： CFRP Remote Laser Cutting Fatigue Process Thermography Process Monitoring

Distinct Global Patterns of Strong Positive and Negative Shifts of Seasons over the Last 6 Decades

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Atmospheric and Climate Sciences 2012年第1期2卷 76-88页

作者： Andres Schmidt Beverly E. Law Chad Hanson Otto klemm 不详

Alterations of annual temperature cycles have profound implications on how the planet responds to global climate change. In this study, a high resolution global analysis of temperature cycle shifts and their development over time is presented. We show that over the last 63 years, phase shifts in the annual near surface temperature cycle exhibit large spatiotemporal variability. The calculated phase shifts comprise earlier onsets of seasons as well as delays with similar frequencies, depending on location. From 1978 to 2010 Eastern Europe experienced an advanced annual cycle of near-surface temperature of 3.2 days while Eastern Australia shows an opposite shift towards later seasons of 3.5 days in comparison to the preceding 30-year period from 1948 to 1977. The largest phase shifts of –5.5 days toward earlier seasons over land were found in Belarus and Northwest Russia. For the first time the developments of seasonal temperature shifts were generalized for large areas by using self-organizing feature map neural networks resulting into 4 significant global trends. The temperature phase shifts are also shown to have strong correlations with the timing of shrub foliation observed at 57 phenological stations across the USA. The findings have far-reaching, yet regionally distinct consequences on agriculture, animal life cycles, plant phenology, and regional weather phenomena that change with annual temperature cycles.

关键词： Climate Change Temperature Phase Shift Neural Networks Phenology Near-Surface Temperature

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基于STEP-NC的数控新标准

合肥工业大学学报（自然科学版） 2008年第1期31卷 131-135页

作者：夏链胡静赵韩 M Wosnik P klemm 合肥工业大学机械与汽车工程学院安徽合肥230009 斯图加特大学机床控制与生产工程研究所巴登-符腾堡斯图加特70174

文章在分析传统数控加工代码标准的主要缺点的基础上,引入了STEP标准与新一代数控标准STEP-NC的概念,并将采用STEP-NC的加工流程与采用传统数控方法的加工流程这两者进行了比较。介绍了STEP-NC简化的抽象数据模型及其EXPRESS-G表示法,... 详细信息

文章在分析传统数控加工代码标准的主要缺点的基础上,引入了STEP标准与新一代数控标准STEP-NC的概念,并将采用STEP-NC的加工流程与采用传统数控方法的加工流程这两者进行了比较。介绍了STEP-NC简化的抽象数据模型及其EXPRESS-G表示法,阐述了STEP-NC数控程序的结构和内容,简要介绍了STEP-NC所涉及的标准的范围和内容,指出了STEP-NC研究仍然面临的问题。

关键词：产品模型数据交换标准数控接口标准 ISO14649,ISO10303

如何采用新一代的激光模切技术满足实际应用之需

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电子工业专用设备 2010年第1期39卷 8-14,44页

作者： Markus klemm Spartanics 3605 Edison PlaceRouing Meadows

激光模切，又名数字模切，既利用高功率激光将激光光束路径上的材料蒸发掉。激光束的开和关，以及激光束的路径都与产品图形的裁切要求一一对应。由于被切割的部分被蒸发掉了，因此，对于剔除细小碎片所需的手工或方式复杂的排废均被省去。

关键词：模切技术激光光束应用高功率激光一一对应激光束蒸发路径

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高温杀虫处理对谷物质量的影响

中国粮油学报 1990年第4期5卷 16-20页

作者：谢晓 K.Mnzing Heinke klemm 商业部情报所联邦德国粮食和马铃薯加工研究院

前言与化学杀虫法相比,谷物的高温杀虫处理以其能保护环境的特点,引起国内外粮食储藏界的关注。长期以来,谷物的热进仓在中国作为一种传统的杀虫方法得到广泛应用。具体方法是,将新收获的谷物呈薄层在50℃的阳光下晾晒,然后将其搬入隔... 详细信息

前言与化学杀虫法相比,谷物的高温杀虫处理以其能保护环境的特点,引起国内外粮食储藏界的关注。长期以来,谷物的热进仓在中国作为一种传统的杀虫方法得到广泛应用。具体方法是,将新收获的谷物呈薄层在50℃的阳光下晾晒,然后将其搬入隔热粮仓,在44～47℃的温度下经历约一周后,即可将害虫全部杀灭,而不影响谷物的营养成分和烘焙特性。

关键词：粮食储藏高温杀虫谷物质量

A Telephone Helpline Assessment of Psychosocial Needs of Adults with Cancer Post Institute of Medicine (IOM) Recommendations

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Open Journal of Nursing 2014年第11期4卷 797-807页

作者： Paula klemm Veronica F. Rempusheski Claudine Jurkovitz Paul Kolm Wei Zhang School of Nursing University of Delaware Newark USA Christiana Care Center for Outcomes Research (CCOR) Value Institute Christiana Care Health System Newark USA

Objective: To explore whether the 2007 IOM recommendations had an impact on the reasons for calls to a cancer telephone helpline and determine the major reasons for calls at two different time periods after the 2007 recommendations. Methods: Caller data with identifiers removed were extracted from a cancer helpline database. Baseline data included calls made to the helpline between April 2, 2008 and September 2, 2009 (Period 1). Then, a second data set was built from data collected between September 3, 2009 and May 2, 2011 (Period 2). Results: The major reasons for calls to the cancer telephone helpline during the two different time periods were the same: financial assistance, helpline services information, coping assistance, support groups, and questions related to treatment. Four of the top five reasons were non-treatment related (i.e., financial issues, helpline services information, coping, and support). Conclusions: The nature of calls to the helpline suggests that the financial and psychosocial needs of people with cancer are not being addressed by healthcare providers. Practice implications: The new “normal” for cancer care includes decisions about complex care coupled with new regulatory and financial constraints. This underscores the importance of focused planning of cancer care across multiple care settings in order to ensure continuity of care for the whole person.

关键词： Cancer Patients Cancer Helpline Psychosocial Needs 2007 IOM Recommendations