bluuebunny/crossref_metadata_2025_split huggingface dataset:
Vacancy‐Rich Ni(OH)2 Drives the Electrooxidation of Amino C−N Bonds to Nitrile C≡N Bonds
Authors: Wang Wenbin , Wang Yutang , Yang Ruoou , Wen Qunlei , Liu Youwen , Jiang Zheng , Li Huiqiao , Zhai Tianyou 
Published: June 2020

AbstractElectrochemical synthesis based on electrons as reagents provides a broad prospect for commodity chemical manufacturing. A direct one‐step route for the electrooxidation of amino C−N bonds to nitrile C≡N bonds offers an alternative pathway for nitrile production. However, this route has not been fully explored with respect to either the chemical bond reforming process or the performance optimization. Proposed here is a model of vacancy‐rich Ni(OH)2 atomic layers for studying the performance relationship with respect to structure. Theoretical calculations show the vacancy‐induced local electropositive sites chemisorb the N atom with a lone pair of electrons and then attack the corresponding N(sp3)−H, thus accelerating amino C−N bond activation for dehydrogenation directly into the C≡N bond. Vacancy‐rich nanosheets exhibit up to 96.5 % propionitrile selectivity at a moderate potential of 1.38 V. These findings can lead to a new pathway for facilitating catalytic reactions in the chemicals industry.
Direct Atomic‐Level Imaging of Zeolites: Oxygen, Sodium in Na‐LTA and Iron in Fe‐MFI
Authors: Mayoral Alvaro , Zhang Qing , Zhou Yi , Chen Pengyu , Ma Yanhang , Monji Taro , Losch Pit , Schmidt Wolfgang , Schüth Ferdi , Hirao Hajime , Yu Jihong , Terasaki Osamu 
Published: June 2020

AbstractZeolites are becoming more versatile in their chemical functions through rational design of their frameworks. Therefore, direct imaging of all atoms at the atomic scale, basic units (Si, Al, and O), heteroatoms in the framework, and extra‐framework cations, is needed. TEM provides local information at the atomic level, but the serious problem of electron‐beam damage needs to be overcome. Herein, all framework atoms, including oxygen and most of the extra‐framework Na cations, are successfully observed in one of the most electron‐beam‐sensitive and lowest framework density zeolites, Na‐LTA. Zeolite performance, for instance in catalysis, is highly dependent on the location of incorporated heteroatoms. Fe single atomic sites in the MFI framework have been imaged for the first time. The approach presented here, combining image analysis, electron diffraction, and DFT calculations, can provide essential structural keys for tuning catalytically active sites at the atomic level.
Reaktionen in Tirapazamin induziert durch die Anlagerung von niederenergetischen Elektronen: Dissoziation versus Roaming von OH
Authors: Arthur‐Baidoo Eugene , Ameixa João , Ziegler Patrick , Ferreira da Silva Filipe , Ončák Milan , Denifl Stephan 
Published: June 2020

AbstractTirapazamin (TPZ) wurde aufgrund seiner potenziell hochselektiven Toxizität gegenüber hypoxischen Tumorzellen in klinischen Studien zur Radio‐Chemotherapie getestet. Dabei wurde vorgeschlagen, dass sich entweder das Hydroxyl‐Radikal oder das Benzotriazinyl‐Radikal nach der anfänglichen Reduktion von TPZ als bioaktives Radikal bildet. In dieser Arbeit beschäftigten wir uns mit der niederenergetischen Elektronenanlagerung an TPZ in der Gasphase und untersuchten die Zersetzung des gebildeten TPZ‐Anions mittels Massenspektrometrie. Wir beobachteten die Bildung des (TPZ‐OH)− Anions, begleitet von der Abspaltung des Hydroxyl‐radikals als dem bei weitem häufigsten Reaktionsweg. Quanten‐chemische Berechnungen legen nahe, dass die NH2‐Pyramidalisierung die Schlüsselkoordinate für die Reaktions‐dynamik bei Elektronenanlagerung ist. Für andere beobachtete Reaktionskanäle schlagen wir einen OH‐Roaming‐Mechanismus vor, der in Konkurrenz zur OH‐Dissoziation steht.
Copper‐Catalyzed Borylative Couplings with C−N Electrophiles
Authors: Talbot Fabien J. T. , Dherbassy Quentin , Manna Srimanta , Shi Chunling , Zhang Shibo , Howell Gareth P. , Perry Gregory J. P. , Procter David J. 
Published: June 2020

AbstractCopper‐catalyzed borylative multicomponent reactions (MCRs) involving olefins and C−N electrophiles are a powerful tool to rapidly build up molecular complexity. The products from these reactions contain multiple functionalities, such as amino, cyano and boronate groups, that are ubiquitous in medicinal and process chemistry programs. Copper‐catalyzed MCRs are particularly attractive because they use a relatively abundant and non‐toxic catalyst to selectively deliver high‐value products from simple feedstocks such as olefins. In this Minireview, we explore this rapidly emerging field and survey the borylative union of allenes, dienes, styrenes and other olefins, with imines, nitriles and related C−N electrophiles.
Thermally Activated Adsorption in Metal–Organic Frameworks with a Temperature‐Tunable Diffusion Barrier Layer
Authors: Tan Kui , Jensen Stephanie , Wang Hao , Feng Liang , Wei Kevin , Zhou Hong‐Cai , Li Jing , Thonhauser Timo 
Published: June 2020

AbstractModification of the external surfaces of metal–organic frameworks offers a new level of control over their adsorption behavior. It was previously shown that capping of MOFs with ethylenediamine (EDA) can effectively retain small gaseous molecules at room temperature. Reported here is a temperature‐induced variation in the capping‐layer gate‐opening mechanism through a combination of in situ infared experiments and ab initio simulations of the capping layer. An atypical acceleration and increase in the loading of weakly adsorbed molecules upon raising the temperature above room temperature is observed. These findings show the discovery of novel temperature‐dependent kinetics that goes beyond standard kinetics and suggest a new avenue for tailoring selective adsorption by thermally tuning the surface barrier.
The Direct Partial Oxidation of Methane to Dimethyl Ether over Pt/Y2O3Catalysts Using an NO/O2Shuttle
Authors: Vargheese Vibin , Kobayashi Yasukazu , Oyama S. Ted 
Published: June 2020

AbstractUsing a mixture of NO + O2as the oxidant enabled the direct selective oxidation of methane to dimethyl ether (DME) over Pt/Y2O3. The reaction was carried out in a fixed bed reactor at 0.1 MPa over a temperature range of 275–375 °C. During the activity tests, the only carbon‐containing products were DME and CO2. The DME productivity (μmol gcat−1 h−1) was comparable to oxygenate productivities reported in the literature for strong oxidants (N2O, H2O2, O3). The NO + O2mixture formed NO2, which acted as the oxygen atom carrier for the ultimate oxidant O2. During the methane partial oxidation reaction, NO and NO2were not reduced to N2. In situ FTIR showed the formation of surface nitrate species, which are considered to be key intermediate species for the selective oxidation.
Crystallization‐Driven Asymmetric Helical Assembly of Conjugated Block Copolymers and the Aggregation Induced White‐light Emission and Circularly Polarized Luminescence
Authors: Xu Lei , Wang Chao , Li Yan‐Xiang , Xu Xun‐Hui , Zhou Li , Liu Na , Wu Zong‐Quan 
Published: June 2020

AbstractControlling the self‐assembly morphology of π‐conjugated block copolymer is of great interesting. Herein, amphiphilic poly(3‐hexylthiophene)‐block‐poly(phenyl isocyanide)s (P3HT‐b‐PPI) copolymers composed of π‐conjugated P3HT and optically active helical PPI segments were readily prepared. Taking advantage of the crystallizable nature of P3HT and the chirality of the helical PPI segment, crystallization‐driven asymmetric self‐assembly (CDASA) of the block copolymers lead to the formation of single‐handed helical nanofibers with controlled length, narrow dispersity, and well‐defined helicity. During the self‐assembly process, the chirality of helical PPI was transferred to the supramolecular assemblies, giving the helical assemblies large optical activity. The single‐handed helical assemblies of the block copolymers exhibited interesting white‐light emission and circularly polarized luminescence (CPL). The handedness and dissymmetric factor of the induced CPL can be finely tuned through the variation on the helicity and length of the helical nanofibers.
The fabrication of flexible and oxygen barrier cellulose nanofiber/polylactic acid nanocomposites using cosolvent system
Authors: Jung Bich Nam , Jung Hyun Wook , Kang Dong Ho , Kim Gi Hong , Lee Miji , Shim Jin Kie , Hwang Sung Wook 
Published: June 2020

AbstractThe main disadvantages of polylactic acid (PLA) for food packaging applications are its brittleness and poor gas barrier properties. The purpose of this study is to evaluate the potential usability of triethyl citrate (TEC) and cellulose nanofiber (CNF) in PLA to obtain bio‐based films with optimal properties. The incorporation of CNF as reinforcement fillers in polymer matrix has long been debated due to its difficulties to disperse uniformly in hydrophobic polymer matrix attribute to their hydrophobic nature. In order to overcome this problem, different feeding method for CNF into the mixer was studied, and CNF/PLA nanocomposites were characterized. It was found that CNF was successfully dispersed in the PLA matrix through the TEC‐CNF suspension, which greatly improved tensile strength and flexibility of the CNF/PLA nanocomposites. The oxygen barrier property was enhanced up to 47.3% (16.99 cc·mm/m2·day·atm) with the increase loading of 0.25, 0.50, and 1 wt% of CNF. Moreover, the dynamic mechanical analysis showed that the low tan delta peak of CNF/PLA nanocomposites (48.25°C) was shifted to high peak (52.99°C) due to incorporation of TEC; indicates an improved of thermal stability of the composites. Overall, the t‐CNF/PLA nanocomposites show a great feasibility for various eco‐friendly flexible packaging applications.
Regulation of Cathode‐Electrolyte Interphase via Electrolyte Additives in Lithium Ion Batteries
Authors: Wang Xiao‐Tong , Gu Zhen‐Yi , Li Wen‐Hao , Zhao Xin‐Xin , Guo Jin‐Zhi , Du Kai‐Di , Luo Xiao‐Xi , Wu Xing‐Long 
Published: June 2020

AbstractAs the power supply of the prosperous new energy products, advanced lithium ion batteries (LIBs) are widely applied to portable energy equipment and large‐scale energy storage systems. To broaden the applicable range, considerable endeavours have been devoted towards improving the energy and power density of LIBs. However, the side reaction caused by the close contact between the electrode (particularly the cathode) and the electrolyte leads to capacity decay and structural degradation, which is a tricky problem to be solved. In order to overcome this obstacle, the researchers focused their attention on electrolyte additives. By adding additives to the electrolyte, the construction of a stable cathode‐electrolyte interphase (CEI) between the cathode and the electrolyte has been proven to competently elevate the overall electrochemical performance of LIBs. However, how to choose electrolyte additives that match different cathode systems ideally to achieve stable CEI layer construction and high‐performance LIBs is still in the stage of repeated experiments and exploration. This article specifically introduces the working mechanism of diverse electrolyte additives for forming a stable CEI layer and summarizes the latest research progress in the application of electrolyte additives for LIBs with diverse cathode materials. Finally, we tentatively set forth recommendations on the screening and customization of ideal additives required for the construction of robust CEI layer in LIBs. We believe this minireview will have a certain reference value for the design and construction of stable CEI layer to realize desirable performance of LIBs.
Bayesian profiling for cost with zeros to decompose total cost into probability of cost and mean nonzero cost
Authors: Grunwald Gary K. , Arnett James A. , Liu Wenhui , Ho P. Michael 
Published: June 2020

AbstractCost of health care can vary substantially across hospitals, centers, or providers. Data from electronic health records provide information for studying patterns of cost variation and identifying high or low cost centers. Cost data often include zero values when patients receive no care, and joint two‐part models have been developed for clustered cost data with zeros. Standard methods for center comparisons, sometimes called profiling, can use these methods to incorporate zero values into total cost. However, zero costs also provide opportunities to further examine sources of cost variation and outliers. For example, a hospital may have high (or low) cost due to frequency of nonzero cost, amount of nonzero cost, or a combination of those. We give methods for decomposing hospital differences in total cost with zeros into components for probability of use (i.e., of nonzero cost) and for cost of use (mean of nonzero cost). The components multiply to total cost and quantify components on the same easily interpreted multiplicative scales. The methods are based on Bayesian hierarchical models and counterfactual arguments, with Markov chain Monte Carlo estimation. We used simulated data to illustrate use, interpretation, and visualization of the methods in diverse situations, and applied the methods to 30,024 patients at 57 US Veterans Administration hospitals to characterize outlier hospitals in one year cost of inpatient care following a cardiac procedure. Twenty eight percent of patients had zero cost. These methods are useful in providing insight into cost variation and outliers for planning future studies or interventions.
Structural and spectroscopic study of Ho3+‐doped nanotitania host prepared using a sol–gel technique
Authors: Ameen Majida A. , Arif Gashaw K. 
Published: June 2020

AbstractHolmium (Ho3+)‐doped TiO2 solid laser active materials with different concentrations (1, 3, 5, and 7 wt%) of Ho3+ ions were prepared using a sol–gel method. A structural study of the samples using X‐ray diffraction (XRD) revealed the anatase phase of pure and doped TiO2 calcined at 500°C, which is confirmed by (101), (004), (200), (105), (211), (204), (116), (220) and (215) diffraction peaks. XRD analysis showen a deformation along the c‐axis of the anatase lattice constant with doping, and a random change in the grain size of the doped titania with respect to pure samples. The presence of the titania bonds (Ti–O–Ti) and (Ti–O) of pure and Ho3+‐doped samples were confirmed from the FTIR spectroscopy study of the samples. In addition, it was noted that bands around 1338, and 1339 cm−1 belonging to 3, 5, and 7 wt% dopant concentrations, while no band for 1 wt% was observed. UV‐Vis spectrophotometer and spectrofluorophotometer techniques were used to study the optical and spectroscopic characterizations of these samples. It was found that various fluorescence peaks for Ho3+ ions were observed in the UV–vis region under different pump wavelengths. This is a good indication of suitability of the material to be employed as a laser active medium.
Biochemistry course‐based undergraduate research experience: Purification, characterization, and identification of an unknown lactate dehydrogenase isoenzyme
Authors: Chaari Ali , Al‐Ali Dana , Roach James 
Published: June 2020

AbstractEnzyme purification, characterization, and identification are some of the best ways to introduce undergraduate students to many aspects of biochemistry, particularly as part of project‐based learning (PBL). These kinds of multi‐step laboratory experiments not only help students to better understand basic biochemistry concepts but also serve to introduce them to the scaffolded nature of the research environment. A 13‐week enzyme‐based laboratory project was designed as one of three components associated with the course titled Capstone Laboratory, which is delivered to second‐year undergraduate students at Weill Cornell Medicine in Qatar (WCM‐Q). The project incorporated several fundamental biochemical laboratory techniques, such as chromatography, centrifugation, spectrophotometry, electrophoresis, and kinetic assays, as well as enzyme inhibition and bioinformatic exercises. The aims of the project were to first purify, then to quantify, and finally to study a particular lactate dehydrogenase (LDH) isoenzyme extracted from different chicken organs. LDH was selected for investigation because its inhibition has potential as a therapeutic strategy for cancer treatment. Students enrolled in the Capstone Laboratory course were divided into three groups. Each group conducted experiments associated with one of the project's three aims over consecutive 3‐week periods. Relevant data and materials were passed from one group to the next, with individual students writing reports describing the results from their respective collection of experiments. Students in the third and final group gave presentations summarizing the results of the overall project. In the associated bioinformatic exercises, students assessed the similarities and differences between chicken‐sourced and human‐sourced LDH as well as the interaction between the LDH enzyme and the inhibitors. This PBL in biochemistry is a successful addition to the WCM‐Q premedical curriculum because (a) it affords the second‐year premedical students opportunities to improve and develop content knowledge and technical and communication skills, and also (b) it provides an opportunity to engage many of the undergraduate students in research.
The clinical application value of mixed‐reality‐assisted surgical navigation for laparoscopic nephrectomy
Authors: Li Guan , Dong Jie , Wang Jinbao , Cao Dongbing , Zhang Xin , Cao Zhiqiang , Lu Guangming 
Published: June 2020

AbstractPurposeLaparoscopic nephrectomy (LN) has become the preferred method for renal cell carcinoma (RCC). Adequate preoperative assessment or intraoperative navigation is key to the successful implementation of LN. The aim of this study was to evaluate the clinical application value of mixed‐reality–assisted surgical navigation (MRASN) in LN.Patients and MethodsA total of 100 patients with stage T1N0M0 renal tumors who underwent laparoscopic partial nephrectomy (LPN) or laparoscopic radical nephrectomy (LRN) were prospectively enrolled and divided into a mixed‐reality‐assisted laparoscopic nephrectomy (MRALN) group (n = 50) and a non–mixed‐reality‐assisted laparoscopic nephrectomy (non‐MRALN) group (n = 50). All patients underwent renal contrast‐enhanced CT scans. The CT DICOM data of all patients in the MRALN group were imported into the mixed‐reality (MR) postprocessing workstation and underwent holographic three‐dimensional visualization (V3D) modeling and MR displayed, respectively. We adopted the Likert scale to evaluate the clinical application value of MRASN. The consistency of evaluators was assessed using the Cohen kappa coefficient (k).ResultsNo significant differences in patient demographic indicators between the MRALN group and the non‐MRALN group (P > .05). The subjective score of MRASN clinical application value in operative plan formulation, intraoperative navigation, remote consultation, teaching guidance, and doctor‐patient communication were higher in the MRASN group than in the non‐MRASN group (all P < .001). There were significantly more patients for whom LPN was successfully implemented in the MRALN group than in the non‐MRALN group (82% vs 46%, P < .001). The MRALN group had a shorter operative time (OT) and warm ischemia time (WIT) and less estimated blood loss (EBL) than the non‐MRALN group (all P < .001).ConclusionMRASN is helpful for operative plan formulation, intraoperative navigation, remote consultation, teaching guidance, and doctor‐patient communication. MRALN may effectively improve the successful implementation rate of LPN and reduce the OT, WIT, and EBL.
A nomogram for prediction of stage III/IV gastric cancer outcome after surgery: A multicenter population‐based study
Authors: Gao Zhiying , Ni Jing , Ding Hui , Yan Caiwang , Ren Chuanli , Li Gang , Pan Feng , Jin Guangfu 
Published: June 2020

AbstractMost patients with gastric cancer (GC) are first diagnosed at stage III‐IV and surgery resection remains the primary therapeutic modality for these patients. However, clinical staging used for prediction of those patients provides limited information. We collected clinicopathological data and disease‐progression information from 508 patients with stage III‐IV GC at three Chinese hospitals and 1298 patients from the Surveillance, Epidemiology, and End Results database. Based on the stepwise multivariate regression model, we constructed a novel nomogram to predict overall survival (OS). The performance of discrimination for this model was measured using Harrell's concordance index (C‐index) and receiver‐operating characteristic curve (ROC), and was validated using calibration plots. Multivariate Cox regression analyses showed that tumor size, age at diagnosis, N stage, tumor grade, and distant metastases were outstanding independent prognostic factors of stage III‐IV GC. We developed a nomogram based on these five prognostic predictors. In the training set, the C‐index of the nomogram was 0.645 (95% CI: 0.611‐0.679), which was higher than that of the American Joint Committee on Cancer TNM system alone (sixth TNM: 0.544; seventh TNM: 0.575; eighth TNM: 0.568). Similar results were observed in validation cohort. Moreover, calibration blots demonstrated good consistency between the actual and predicted OS probabilities. According to the nomogram, GC individuals could be classified into three groups (low‐, middle‐, and high‐risk) (P < .001). Our nomogram complements the current staging system for prediction of individual prognosis with stage III‐IV GC, and may be helpful for making individualized treatment decisions.
Fabrication of Porous Configurated Ni2P/Ni Foam Catalyst and its Boosted Properties for pH‐universal Hydrogen Evolution Reaction and Efficient Nitrate Reduction
Authors: Huo Siyue , Yang Shuqin , Niu Qianqian , Song Zimo , Yang Fan , Song Laizhou 
Published: June 2020

AbstractNickel phosphide (Ni2P) has been widely explored toward hydrogen evolution reaction (HER) for desirable durability and high performance. Tuning the electronic structures and morphologies of Ni2P plays a pivotal role in the improvement of HER performance. In this work, three Ni2P catalysts were fabricated by different strategies and their HER properties were compared. It was found that the bicontinuous porous structured Ni2P on Ni foam (Ni2P /NF−EHP) prepared using coupled electroless nickel‐phosphorus (Ni−P) plating, hydrothermal synthesis and low temperature phosphorization techniques, exhibits the best catalytic activity and a wide pH adaptability. The overpotential at 10 mA cm−2 and Tafel slope are 78 mV and 33 mV dec−1 in 0.5 M H2SO4, those in 1 M PBS are 125 mV and 93 mV dec−1, and 101 mV and 76 mV dec−1 in 1 M KOH. Additionally, the Ni2P/NF−EHP‐catalyzed HER process is also applicable for nitrate reduction with a remarkable removal efficiency of 92.6 %. This catalyst also exhibits a desirable durability both in HER and nitrate reduction. This work offers an efficient strategy to exploit compatible pH‐universal HER catalysts, explores the engineering application of HER process in nitrate reduction.
36‐Nuclearity Organophosphonate‐Functionalized Polyoxomolybdates: Synthesis, Characterization and Selective Catalytic Oxidation of Sulfides
Authors: Xu Qiaofei , Liang Xinmiao , Xu Baijie , Wang Jiawei , He Peipei , Ma Pengtao , Feng Jiwen , Wang Jingping , Niu Jingyang 
Published: June 2020

AbstractThe crown‐shaped 36‐molybdate cluster organophosphonate‐functionalized polyoxomolybdates with the highest nuclearity in organophosphonate‐based polyoxometalate chemistry, (NH4)19Na7H10[Cu(H2O)TeMo6O21{N(CH2PO3)3}]6⋅31 H2O, has been reported for the first time. The synthesized 36‐molybdate cluster was characterized by routine techniques and tested as a heterogeneous catalyst for selective oxidation of sulfides with impressive catalytic and selective performances after heat treatment. High efficiency (TON=15333) was achieved in the selective oxidation of sulfides to sulfoxides, caused by the synergic effect between copper and polyoxomolybdates and the generation of the cuprous species during the heat treatment.