bluuebunny/crossref_metadata_2025_split huggingface dataset:
Synthesis of Functionalized Cyclobutane‐Fused Naphthalene Derivatives via Cascade Reactions of Allenynes with tert‐Butyl Nitrite
Authors: Feng Tian , He Yan , Zhang Xinying , Fan Xuesen 
Published: January 2019

AbstractA novel synthesis of cyclobutanol‐fused 2‐nitronaphthalen‐1‐ols and nitrocyclobutane‐fused naphthalene‐1,2‐diones through cascade reactions of benzene‐linked allenynes with tert‐butyl nitrite is presented. The formation of the title compounds involves a tandem process including allenyne [2+2] cycloaddition, radical addition onto the in situ formed cyclobutenyl moiety followed by radical coupling/oxidation. Interestingly, different kinds of functionalized naphthalene derivatives could be obtained selectively from the same substrates, and the selectivity was easily controlled by finely tuning the reaction conditions.magnified image
Enhanced Radiosensitization by Gold Nanoparticles with Acid‐Triggered Aggregation in Cancer Radiotherapy
Authors: Zhang Yumin , Huang Fan , Ren Chunhua , Liu Jinjian , Yang Lijun , Chen Shizhu , Chang Jinglin , Yang Cuihong , Wang Weiwei , Zhang Chuangnian , Liu Qiang , Liang Xing‐Jie , Liu Jianfeng 
Published: January 2019

AbstractAn ideal radiosensitizer holding an enhanced tumor retention can play an incredible role in enhancing tumor radiotherapy. Herein, a strategy of acid‐triggered aggregation of small‐sized gold nanoparticles (GNPs) system within tumor is proposed and the resulting GNPs aggregates are applied as a radiosensitizer in vitro and in vivo. The GNPs system with the acid‐triggered aggregation achieves an enhanced GNPs accumulation and retention in cancer cells and tumors in the form of the resulted GNPs aggregates. As a consequence, the radiosensitization effect shows significant improvement in cancer radiotherapy, which is shown in the studies of DNA breakage and the comet assay, and the sensitizer enhancement ratio (SER) value of the GNPs system (1.730) with MCF‐7 cancer cells is much larger than that of the single GNPs (1.16). In vivo antitumor studies reveal that the GNPs system also enhances the sensitivity of MCF‐7 tumor xenograft to radiotherapy. Furthermore, the GNPs aggregates improve the signal of small GNPs in vivo photoacoustic imaging. This study provides a new strategy and insights into fabricating nanoaggregates to magnify the radiosensitive efficiency of nanosystems in cancer radiotherapy.
Tailoring Lithium Deposition via an SEI‐Functionalized Membrane Derived from LiF Decorated Layered Carbon Structure
Authors: Wang Muqin , Peng Zhe , Luo Wenwei , Ren Feihong , Li Zhendong , Zhang Qiang , He Haiyong , Ouyang Chuying , Wang Deyu 
Published: January 2019

AbstractLithium (Li) metal is a key anode material for constructing next generation high energy density batteries. However, dendritic Li deposition and unstable solid electrolyte interphase (SEI) layers still prevent practical application of Li metal anodes. In this work, it is demonstrated that an uniform Li coating can be achieved in a lithium fluoride (LiF) decorated layered structure of stacked graphene (SG), leading to the formation of an SEI‐functionalized membrane that retards electron transfer by three orders of magnitude to avoid undesirable Li deposition on the top surface, and ameliorates Li+ ion migration to enable uniform and dendrite‐free Li deposition beneath such an interlayer. Surface chemistry analysis and density functional theory calculations demonstrate that these beneficial features arise from the formation of C–Fx surface components on the SG sheets during the Li coating process. Based on such an SEI‐functionalized membrane, stable cycling at high current densities up to 3 mA cm−2 and Li plating capacities up to 4 mAh cm−2 can be realized in LiPF6/carbonate electrolytes. This work elucidates the promising strategy of modifying Li plating behavior through the SEI‐functionalized carbon structure, with significantly improved cycling stability of rechargeable Li metal anodes.
Diagnostic impact of high serum midkine level in patients with gastric cancer
Authors: Ito Masaaki , Oshima Yoko , Yajima Satoshi , Suzuki Takashi , Nanami Tatsuki , Shiratori Fumiaki , Funahashi Kimihiko , Shimada Hideaki 
Published: January 2019

AbstractAimWe evaluated the diagnostic impact of serum midkine (s‐MK) levels in patients with gastric cancer using a monoclonal antibody enzyme‐linked immunosorbent assay system (ELISA) to detect s‐MK levels.MethodsSerum samples were obtained from 131 patients with gastric cancer including stage I (n = 71), stage II (n = 28), stage III (n = 16), and stage IV (n = 16) before surgery. Serum samples were analyzed using ELISA to detect soluble midkine. A cut‐off value was fixed at 421 pg/mL, and the sample divided into two groups: a high s‐MK group and a low s‐MK group. Clinicopathological factors and prognosis were compared between these two groups using univariate and multivariate analyses. Comparison of two groups was analyzed by Fisher's exact probability test. Statistical significance was considered at P < 0.05.ResultsHigh s‐MK was significantly associated with high carcinoembryonic antigen (CEA) (P < 0.01). Positive rate of s‐MK was higher than the positive rates of CEA in patients with stage I/II gastric cancer. Combination with CEA + CA19‐9 + s‐MK increased the positive rates of patients with stage I/II gastric cancer. No other clinicopathological factors were associated with s‐MK. Although the high s‐MK group showed worse overall survival than the low s‐MK group, the difference was not statistically significant.Conclusions‐MK level is increased even during early‐stage gastric cancer. Combined with s‐MK, the positive rate of CEA + CA19‐9 was increased in patients with stage I/II gastric cancer.
Fulleren‐gefüllte Flüssigkristall‐Sterne: Ein supramolekularer Klick‐Mechanismus zur Bildung von maßgeschneiderten Donor‐Akzeptor‐Strukturen
Authors: Lehmann Matthias , Dechant Moritz , Holzapfel Marco , Schmiedel Alexander , Lambert Christoph 
Published: January 2019

AbstractZwei formtreue Sternmesogene mit Oligo(phenylenethenylen)‐Armen und einem Phthalocyanin‐Kern wurden erfolgreich synthetisiert. Dabei stellt eines (2) Freiraum bereit, und das andere (3) ist mit vier Fullerenen, die mittels eines Abstandhalters verbunden sind, sterisch überfrachtet. Im Gegensatz zu einem kleineren diskotischen Derivat (1), bildet Mesogen 2 eine kolumnare flüssigkristalline (LC) Phase aus, die keine π‐Stapelung zeigt und nur zum Teil orientiert werden kann, während 3 kein LC ist. Die 1:1‐Mischung von 2 und 3 generiert einen außergewöhnlichen, orientierbaren kolumnaren LC mit deutlicher π‐Stapelung und einer Fulleren‐Quadrupelhelix. Dies ist die Folge eines beispiellosen Klick‐Mechanismus, der einem Kugelarretierungs‐Mechanismus ähnelt. Die C60‐Einheiten verbinden dabei auch unterschiedliche Kolumnen. Dieser Prozess wird durch Nanosegregation und Raumfüllung der Lücken durch die Fullerene angetrieben. Photophysikalische Untersuchungen bestätigen das Vorhandensein eines Lichtsammelsystems, wobei sowohl in Lösung als auch im Festkörper ladungsgetrennte Zustände generiert wurden, was solche hochgeordneten Materialien attraktiv für das Studium in zukünftigen photovoltaischen Zellen macht.
Quaternary Centers by Nickel‐Catalyzed Cross‐Coupling of Tertiary Carboxylic Acids and (Hetero)Aryl Zinc Reagents
Authors: Chen Tie‐Gen , Zhang Haolin , Mykhailiuk Pavel K. , Merchant Rohan R. , Smith Courtney A. , Qin Tian , Baran Phil S. 
Published: January 2019

AbstractThis work bridges a gap in the cross‐coupling of aliphatic redox‐active esters with aryl zinc reagents. Previously limited to primary, secondary, and specialized tertiary centers, a new protocol has been devised to enable the coupling of general tertiary systems using nickel catalysis. The scope of this operationally simple method is broad, and it can be used to simplify the synthesis of medicinally relevant motifs bearing quaternary centers.
From As‐Zincoarsasilene (LZn‐As=SiL′) to Arsaethynolato (As≡C−O) and Arsaketenylido (O=C=As) Zinc Complexes
Authors: Ballestero‐Martínez Ernesto , Szilvási Tibor , Hadlington Terrance J. , Driess Matthias 
Published: January 2019

AbstractThe reactivity of the As‐zincosilaarsene LZn−As=SiL′ A (L=[CH(CMeNDipp)2]−, Dipp=2,6‐iPr2C6H3, L′=[{C(H)N(2,6‐iPr2‐C6H3)}2]2−) towards small molecules was investigated. Due to the pronounced zwitterionic character of the Si=As bond of A, it undergoes addition reactions with H2O and NH3, forming LZnAs(H)SiOH(L′) 1 and LZnAs(H)SiNH2(L′) 2. Oxygenation of A with N2O at −60 °C furnishes the deep blue 1,2‐disiloxydiarsene, [LZnOSi(L′)As]2 4, presumably via dimerization of the arsinidene intermediate LZnOSi(L′)As 3. Oxygenation of A with CO2 leads to the monomeric arsaethynolato siloxido zinc complex LZnOSi(L′)(OC≡As) 5, essentially trapping the intermediary arsinidene 3 with liberated CO following initial oxidation of the Si=As bond. DFT calculations confirm the ambident coordination mode of the anionic [AsCO] ligand in solution, with the O‐arsaethynolato [As≡C−O].− in 5, and the As‐arsaketenylido ligand mode [O=C=As]− present in LZnO−Si(L′)(−As=C=O) 5′ akin to the analogous phosphorus system, [PCO]−.
Regiodivergent Hydroaminoalkylation of Alkynes and Allenes by a Combined Rhodium and Photoredox Catalytic System
Authors: Zheng Jun , Breit Bernhard 
Published: January 2019

AbstractA rhodium/photoredox dual catalyzed regiodivergent α‐allylation of amines is described. As an atom‐economic and efficient method, alkynes and allenes are used as allylic electrophile surrogates in this novel protocol. With different reaction conditions, synthetically useful branched or linear homoallylic amines could be synthesized in good to excellent yields and regioselectivity. This straightforward strategy complements the traditional transition‐metal catalyzed allylation reactions.
Approaching the Lithiation Limit of MoS2 While Maintaining Its Layered Crystalline Structure to Improve Lithium Storage
Authors: Zhu Zhiqiang , Tang Yuxin , Leow Wan Ru , Xia Huarong , Lv Zhisheng , Wei Jiaqi , Ge Xiang , Cao Shengkai , Zhang Yanyan , Zhang Wei , Zhang Hongwei , Xi Shibo , Du Yonghua , Chen Xiaodong 
Published: January 2019

AbstractMoS2 holds great promise as high‐rate electrode for lithium‐ion batteries since its large interlayer can allow fast lithium diffusion in 3.0–1.0 V. However, the low theoretical capacity (167 mAh g−1) limits its wide application. Here, by fine tuning the lithiation depth of MoS2, we demonstrate that its parent layered structure can be preserved with expanded interlayers while cycling in 3.0–0.6 V. The deeper lithiation and maintained crystalline structure endows commercially micrometer‐sized MoS2 with a capacity of 232 mAh g−1 at 0.05 A g−1 and circa 92 % capacity retention after 1000 cycles at 1.0 A g−1. Moreover, the enlarged interlayers enable MoS2 to release a capacity of 165 mAh g−1 at 5.0 A g−1, which is double the capacity obtained under 3.0–1.0 V at the same rate. Our strategy of controlling the lithiation depth of MoS2 to avoid fracture ushers in new possibilities to enhance the lithium storage of layered transition‐metal dichalcogenides.
Characterization of a novel silicon‐containing hybrid polymer by thermal curing, pyrolysis behavior, and fluorescence analysis
Authors: Chen Mingfeng , Liu Yuhui , Lin Jinhuo , Liu Canpei 
Published: January 2019

ABSTRACTA novel linear silicon‐containing hybrid polymer with C  C and SiH linkages, diphenyl‐dihydroethynyl‐silane (DPHES), had been conveniently synthesized and well characterized. The thermal curing, crosslinked structure and pyrolysis behavior were studied by DSC, Fourier transform infrared (FTIR), and Pyrolysis‐gas chromatography/mass spectrometry (Py‐GC/MS). The results suggest the crosslinked structures consist mainly of phenyl and aromatic fused rings, which are formed through cyclotrimerization, addition reaction, and hydrosilylation reaction. The thermal properties indicate that the crosslinked DPHES exhibits excellent thermal stability with the temperature at 5% weight loss are higher than 572 and 509 °C under nitrogen and air atmosphere, respectively. The fluorescence emission spectra show DPHES and its crosslinked product also have moderate fluorescence properties, emitting purple light, and visible blue light, respectively, which further verified the structure of DPHES. These results suggest that DPHES has the potential to be used as light‐emitting materials with excellent thermal properties. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47403.
Ternary nanocomposites based on epoxy, modified silica, and tetrabutyl titanate: Morphology, characteristics, and kinetics of the curing process
Authors: Minh Ho Ngoc , Chinh Nguyen Thuy , Thanh Van Tran Thi , Hoang Thai 
Published: January 2019

ABSTRACTIn this study, the effects of unmodified nanosilica and nanosilica modified by an isopropyl tri[di(octyl) phosphate] titanate coupling agent (KR‐12;m‐nanosilica) on the structure, morphology, thermomechanical properties, and kinetics of the curing process of epoxy–tetrabutyl titanate (TBuT) nanocomposites were investigated. The viscosity, tensile strength, and flexural strength of the cured epoxy and cured epoxy–m‐silica–TBuT nanocomposites were determined with a Brookfield viscometer and an Instron 5582‐100KN universal machine. The morphology and gel fraction content of the nanocomposites were analyzed with transmission electron microscopy and scanning electron microscopy methods and Soxhlet extraction. The viscosity, mechanical properties, gel fraction content, and morphology results of the cured epoxy–m‐silica–TBuT nanocomposites confirm that 5 wt %m‐nanosilica was the most suitable for improving the dispersion ofm‐nanosilica in the epoxy matrix and the properties of these materials. The thermal behavior of the nanocomposites was determined by thermogravimetric analysis and differential scanning calorimetry (DSC) methods. On the basis of DSC data, the average value of the activation energy of the cured epoxy–TBuT system, calculated according to Flynn–Wall–Ozawa and Kissinger equations, was 67.893 kJ/mol. The calculation according to the Crane equation showed that the first‐order kinetics complied with the curing reaction for the neat epoxy. When we introduced the unmodified nanosilica and modified nanosilica into the epoxy matrix, the order kinetics of the curing reaction for the nanocomposites also followed first‐order kinetics, but the activation energy of their curing reaction decreased significantly. Some other properties were also investigated with dynamic mechanical analysis and Fourier transform infrared analysis and are discussed. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47412.
Regeneration and utilization of waste phenolic formaldehyde resin: A performance investigation
Authors: Yang Lve , Runt James , Kuo Mu‐chen , Huang Kuo‐shien , Yeh Jen‐taut 
Published: January 2019

ABSTRACTRecycled thermosetting phenolic formaldehyde (RPF) resins were pulverized to micron‐sized powders and successfully reused as an effective component by reactive‐injecting with neat phenolic formaldehyde (PF) and/or trioxymethylene (TOX) to prepare regenerated phenolic formaldehyde (i.e., and ). Tensile strength (σf), impact strength (Is), and density (ρ) of and specimens were reduced as RPF concentrations or average particle sizes increased. It is worth emphasizing that σf, Is, and ρ of each reaction‐injected series having a fixed RPF concentration and average particle size improved to a maximum value, as TOX concentrations reached a corresponding optimal value. This is the first investigation to report that σf and Is of proper regenerated PF/RPF/TOX specimens using ≦20 wt % RPF waste were ≥ 95% of those of the virgin reaction‐injected PF. Possible reasons accounting for these improved mechanical properties were proposed based on results from their Fourier transform infrared analysis (FTIR). © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47445.
Silica nanoparticles reinforced natural rubber latex composites: The effects of silica dimension and polydispersity on performance
Authors: Xia Lijian , Song Jianhui , Wang Hui , Kan Ze 
Published: January 2019

ABSTRACTThe nano‐size autonomous monodisperse silica (AS) particles were prepared by hydrolysis and condensation of tetraethoxysilane usingl‐lysine as catalyst. The silica/natural rubber (NR) masterbatches were then produced via latex compounding, in which NR latex was mixed with the above AS dispersion. The commercial precipitated silica (PS) was introduced as a control. The effects of both AS and PS particles on the interfacial and mechanical properties of composites were systematically examined. It was found that the AS formed bead‐like morphology wherein the clear particle edges can be distinguished in rubber matrix. Compared with PS/NR, the AS/NR composites were proved to possess more bound rubber and weaker filler–filler interaction resulting in higher tensile strength, abrasive resistance, and resilience. Meanwhile, the efficiency of premodified AS and PS surfaces using bis‐(3‐triethoxysilylpropyl) tetrasulfide on reinforcing the properties of silica/NR composites was studied. The results presented that the overall properties of modified silica/NR vulcanizates were improved significantly. In special, the values of heating building‐up and compression set showed an evident decline which was of great significance for tire tread or other rubber products. For the dynamic properties, the magic angle spinning/NR composites had lower rolling resistance. In short, AS may be applied as an ideal substitution of PS in rubber. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2019,136, 47449.
Preparation of silica/epoxy hybrid polymers as sealing layers on ceramic coatings and their stability study upon thermal treatment
Authors: Wang Yuye , Wang Jinwei 
Published: January 2019

ABSTRACTAmine end silica sol (NH2‐silica) was prepared to react with epoxy to make hybrid polymers. With the addition of NH2‐silica, the viscosity exhibited a declining trend until their amount reached around 20%. The hybrids possessed higher decomposing temperatures and higher residues relative to neat epoxy in air; their decomposing behaviors depended on the silica additions, attributing to the joint effects of incorporation of Si‐O segments and unstable state of silica sol upon heating. When these hybrids were brushed on ceramic coatings, they infiltrated into a depth of around 60 μm. As sealing layers, they probably experienced partially decomposing, slumping, and then filling the internal defects of the ceramic coatings, some hybrid residue even moved to the boundary areas adjacent to the steel substrates after repeated heating. These hybrids may be applied as sealants on ceramic coatings to prolong the lifespan of steel construction structure at high temperature. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019, 136, 47481.
Bi‐heterocyclic benzamides as alkaline phosphatase inhibitors: Mechanistic comprehensions through kinetics and computational approaches
Authors: Abbasi Muhammad A. , Nazir Majid , ur‐Rehman Aziz , Siddiqui Sabahat Z. , Hassan Mubashir , Raza Hussain , Shah Syed A. A. , Shahid Muhammad , Seo Sung‐Yum 
Published: January 2019

AbstractNovel bi‐heterocyclic benzamides were synthesized by sequentially converting 4‐(1H‐indol‐3‐yl)butanoic acid (1) into ethyl 4‐(1H‐indol‐3‐yl)butanoate (2), 4‐(1H‐indol‐3‐yl)butanohydrazide (3), and a nucleophilic 5‐[3‐(1H‐indol‐3‐yl)propyl]‐1,3,4‐oxadiazole‐2‐thiol (4). In a parallel series of reactions, various electrophiles were synthesized by reacting substituted anilines (5a–k) with 4‐(chloromethyl)benzoylchloride (6) to afford 4‐(chloromethyl)‐N‐(substituted‐phenyl)benzamides (7a–k). Finally, the nucleophilic substitution reaction of 4 was carried out with newly synthesized electrophiles, 7a–k, to acquire the targeted bi‐heterocyclic benzamides, 8a–k. The structural confirmation of all the synthesized compounds was done by IR, 1H NMR, 13C NMR, EI‐MS, and CHN analysis data. The inhibitory effects of these bi‐heterocyclic benzamides (8a–k) were evaluated against alkaline phosphatase, and all these molecules were identified as potent inhibitors relative to the standard used. The kinetics mechanism was ascribed by evaluating the Lineweaver–Burk plots, which revealed that compound 8b inhibited alkaline phosphatase non‐competitively to form an enzyme–inhibitor complex. The inhibition constant Ki calculated from Dixon plots for this compound was 1.15 μM. The computational study was in full agreement with the experimental records and these ligands exhibited good binding energy values. These molecules also exhibited mild cytotoxicity toward red blood cell membranes when analyzed through hemolysis. So, these molecules might be deliberated as nontoxic medicinal scaffolds to render normal calcification of bones and teeth.
Contemporary Prevalence of Gout and Hyperuricemia in the United States and Decadal Trends: The National Health and Nutrition Examination Survey, 2007–2016
Authors: Chen‐Xu Michael , Yokose Chio , Rai Sharan K. , Pillinger Michael H. , Choi Hyon K. 
Published: January 2019

ObjectiveTo estimate the current prevalence rates and decadal trends of gout and hyperuricemia in the US, as well as the prevalence of urate‐lowering therapy (ULT) among gout patients, using 2007–2016 data from a nationally representative survey of American men and women (the National Health and Nutrition Examination Survey [NHANES]).MethodsUsing data from 5,467 participants in the NHANES 2015–2016, we estimated the most recent prevalence rates of gout and hyperuricemia. When the NHANES was conducted, all participants were asked about their history of gout (as diagnosed by a health professional) and medication use. Hyperuricemia was defined as having a serum urate level of >7.0 mg/dl in men and >5.7 mg/dl in women. We examined decadal trends in these estimates using data from the NHANES 2007–2016 and investigated ULT usage trends using the NHANES 2007–14 (the most recent data available to date).ResultsIn 2015–2016, the prevalence of gout was 3.9% among adults in the US (9.2 million people), with 5.2% [5.9 million] in men and 2.7% [3.3 million] in women. Mean serum urate levels were 6.0 mg/dl in men and 4.8 mg/dl in women, and hyperuricemia prevalence rates were 20.2% and 20.0%, respectively. The prevalence rates of gout and hyperuricemia remained stable between 2007 and 2016 (P for trend > 0.05). The prevalence of ULT use among patients with gout was 33% in 2007–2014 and remained stable over time (P for trend > 0.05).ConclusionIn this nationally representative survey sample of adults in the US, the prevalence rates of gout and hyperuricemia remained substantial, albeit unchanged, between 2007 and 2016. Despite these rates, only one‐third of gout patients were receiving ULT.
A Dinuclear Dysprosium Complex as an Air‐Stable and Recyclable Catalyst: Applications in the Deacetylation of Carbohydrate, Aliphatic, and Aromatic Molecules
Authors: Chiu Ting‐Yu , Chin Wei , Guo Jiun‐Rung , Liang Chien‐Fu , Lin Po‐Heng 
Published: January 2019

AbstractTwo dinuclear DyIII complexes, [Dy2(hmb)2(OTf)2(H2O)4]⋅HOTf⋅2 THF (A⋅HOTf⋅2 THF) and [Dy2(hmi)3(H2O)2]⋅2 HOTf (B⋅2 HOTf), have been synthesized by the reaction of Dy(OTf)3 and the Schiff‐base ligands H2hmb (N′‐(2‐hydroxy‐3‐methoxybenzylidene)benzohydrazide) or H2hmi ((2‐hydroxy‐3‐methoxyphenyl)methylene isonicotinohydrazine). Disarmed glycosyl trichloroacetimidates can be activated by complex A in the synthesis of 1,2‐trans‐glycosides with primary and secondary acceptors. This method offers an efficient route to selectively deacetylated monosaccharides and disaccharides in high yields and a green catalyst that can be easily recycled and reused.