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Despite the great prospects of alkali metal batteries, safety concerns associated with dendrite growth still limit their commercial applications. An attractive alternative is to use the room temperature liquid sodium–potassium alloy as the anode, which inherently prevents dendrite growth. Currently, Na–K alloy anodes allow only Na+ or K+ to be cycled, depending on the choice of electrolyte and ion selectivity of the cathode, which results in reduced energy density of the battery. Herein, the possibility of concurrent use of both Na+ and K+ ions in Na–K alloy anodes is explored, and the working mechanism by operando optical microscopy is investigated. It is found that the type of deposited metal is dictated by both salt and solvent in electrolyte. Impressively, Na–K co‐deposition is observed in KFSI‐DME electrolyte for the first time, which strongly influences the dendrite morphology and evolution. Furthermore, the current density also has a great impact on the deposition pattern, which allows dendrite‐free Na/K deposition on the liquid‐alloy anode. These findings enrich our understanding of the intricate electrochemical behaviors of Na–K binary electroactive alloy systems and offer guidance for the sufficient use of Na and K while avoiding dendrite formation in such liquid‐alloy batteries.

Abstract Single‐component semiconductors with photoresponse to full solar spectrum are highly desirable to simplify the device structure of commercial photodetectors and to improve solar conversion or photocatalytic efficiency but remain scarce. This work reports bottom‐up photosynthesis of an air‐stable radical semiconductor using BiI3 and a photochromism‐active benzidine derivative as a photosensitive functional motif. This semiconductor shows photoconductivity to full solar spectrum contributed by radical and non‐radical forms of the benzidine derivative. It has also the potential to detect X‐rays because of strong X‐ray absorption coefficient. This finding opens up a new synthetic method for radical semiconductors and may find applications on extending photoresponsive ranges of perovskites, transition metal sulfides, and other materials.

The mechanism of lithium dendrites penetrating solid electrolytes remains elusive. Herein, the authors reveal the Li deposition dynamics and the associated failure mechanism of solid electrolyte by visualizing the Li|LLZO interface evolution via in situ transmission electron microscopy.

Suppressing phase transitions is crucial for the layered lithium/sodium transition metal oxide cathodes in batteries. Here, the authors report a water-mediated strategy to mitigate the phase transitions and boost electrochemical performances of manganese-based layered cathodes for cost-effective Na-ion batteries.

Air-stability is a critical challenge faced by layered sodium transition metal oxide cathodes. Here, the authors depict a general and in-depth model of the structural/chemical evolution of P2-type layered oxides in air and propose an evaluation rule for the air-stability of layered sodium cathodes.

Developing new materials with broadband photoresponse is highly desirable for realizing commercial photodetectors with extended detection ranges. Here, the authors report a cyanide-bridged layer-directed intercalation approach to design viologen compounds with enhanced broadband photoresponse.

One of the crucial challenges for applying Sn as an anode of lithium-ion batteries (LIBs) is the dramatic volume change during lithiation/delithiation process, which causes a rapid capacity fading and then deteriorated battery performance. To address this issue, herein, we report the design and fabrication of Sn encapsulated carbon nanoboxes (denoted as Sn@C) with yolk@shell architectures. In this design, the carbon shell can facilitate the good transport kinetics whereas the hollow space between Sn and carbon shell can accommodate the volume variation during repeated charge/discharge process. Accordingly, this composite electrode exhibits a high reversible capacity of 675 mAh g−1 at a current density of 0.8 A g−1 after 500 cycles and preserves as high as 366 mAh g−1 at a higher current density of 3 A g−1 even after 930 cycles. The enhanced electrochemical performance can be ascribed to the crystal size reduction of Sn cores and the formation of polymeric gel-like layer outside the electrode surface after long-term cycles, resulting in improved capacity and enhanced rate performance.

Linear transformation shift registers (TSR) were introduced by Tsaban and Vishne,which was a word-oriented shift register output a word per step.Some basic properties of sequences generated by the TSR were presented,and a new criterion for deciding if the characteristic polynomial of a TSR system is irreducible was given.This criterion avoids operations in extension fields.

Hard carbons hold great promise as the anode materials for sodium-ion batteries (SIBs), but the limited capacities and sluggish Na+ transfer kinetics still hinder their practical applications. These issues can be addressed from the perspective of improving the wettability of hard carbons with electrolyte. Herein, we demonstrate that the wettability of hard carbons can be regulated by tuning their pore size, so as to optimize their electrochemical properties. A series of N-doped hollow mesoporous carbon nanotubes (HMCNTs) with the average pore sizes in the range of 2–8 nm are synthesized. Among them, the HMCNTs with an average pore size of 6.1 nm (HMCNTs-6.1) exhibits the most improved wettability and reaction kinetics, which delivers a high reversible capacity (415.5 mA h g−1 after 100 cycles at 0.1 A g−1), superior long-term cycle stability and rate capability. In addition, as visualized by in situ transmission electron microscopy, the HMCNTs-6.1 with relatively large mesopores is more favorable for the mass transport across the carbon shells than the HMCNTs with smaller pore sizes. This work provides new insight for understanding the relationship between pore size, electrolyte wettability and electrochemical performance of porous hard carbon, which can help to design the high-performance SIB anodes. [ABSTRACT FROM AUTHOR]

Three novel silver complexes with a 1-D to 3-D architecture constructed through ligand-unsupported argentophilic interactions are solvothermally synthesized. These three complexes are revealed to be potential luminescent materials.

Post-synthesis carbon doping of individual boron nitride nanotubes (BNNTs) is achieved via in situ electron-beam irradiation inside an energy-filtering 300 eV high-resolution transmission electron microscope. The substitution of C for B and N atoms in the honeycomb lattice is shown through electron energy loss spectroscopy and substitutional C doping has transformed BNNTs from electrical insulators to conductors.

A direct white-light metal-organic framework (MOF), [[AgL].sub.n].n[H.sub.2]O (L = 4-cyanobenzoate), obtained by the reaction of deprotonated 4-cyanobenzoic acid and AgN[O.sub.3] in water, has displayed tunable yellow-to-white photoluminescence by variation of excitation light. The close pure white emission of [[AgL].sub.n].n[H.sub.2]O has CIE-1931 chromaticity coordinates of (0.33, 0.34) when excited by 349-nm ultraviolet light, which is shown to be compatible to the light output of the deep UV LED.

The hydrothermal reaction of Mn[Cl.sub.2].4[H.sub.2]O with N,N-bis[1(2)-H-tetrazol-5-yl]amine ([H.sub.2]bta) in different pH values were used to prepare two novel manganese(II) tetrazolate coordination polymers, [Mn.sub.3][(Hbta).sub.4][([[mu].sub.2]-OH).sub.2]([H.sub.2]O).2[H.sub.2]O and Mn(bta)([H.sub.2]O). The results from magnetic measurements indicated that [Mn.sub.3][(Hbta).sub.4][([[mu].sub.2]-OH).sub.2]([H.sub.2]O).2[H.sub.2]O displays an antiferromagnetic ordering while compound Mn(bta)([H.sub.2]O) exhibits the coexistence of a spin-canted antiferromagnetic coupling and a field-induced spin-flop transition.

A novel zinc(II) 4-(5H-tetrazo)benzoic coordination polymer with an in situ generated tetrazole ligand has displayed the gsi ([gamma]-silicon) topology and high thermal stability. This compound has second-order nonlinear optical and heat-induced photoluminescent properties.

The synthesis and characterization of a new quaternary mercury and cadmium pnictidehalide semiconductor, ([Hg.sub.6][Sb.sub.4])(Cd[I.sub.6]) which could be used for applications as efficient photovoltaic materials and window materials for laser delivery media is reported.

A novel two dimensional metal-organic framework with a topology that defines the highest connectivity of known 2 dimensional nets is constructed using octanuclear cobalt clusters as 10 connected nodes and organic ligands as 3- connected nodes as well as 'double-bridge' linkers.

A facile approach, a ball-milling reaction method, is used to design and regulate the fabrication of 14 dinuclear and 2-D cyano-bridged 4f-3d hexacyanometallates. Diamagnetism along with isomorphous structures of the [Co.sup.3+] and [La.sup.3+] ions provide an estimate of the nature of coupling between the iron (III) and lanthanide(III) ions in the [La.sup.3+]- [Fe.sup.3+] complexes.

Synthesis of a new series of quaternary metal chalcogenides containing group 13 elements by a reactive flux method is described. The energy band gaps are larger than those of chalcopyrites. The compounds are capable of absorbing solar radiation and lack infrared absorption property.

Many caregivers of individuals who are frail and elderly face financial hardships that have negative consequences that compound over time. This article explores the causes of these hardships, reviews Medicaid home and community-based interventions, and related government financial supports that have been used to alleviate them and concludes with recommendations for social work practice and social policy. [ABSTRACT FROM AUTHOR]

Using data from a national sample of 451 single mothers collected 24 months during and after the Great Recession, this study tested four hypotheses related to comprehensive measures of employment problems, number of months without health insurance, and unmet medical or dental needs. The results indicate positive relationships between employment problems and unmet medical or dental needs, employment problems and lacking health insurance, and lacking health insurance and unmet medical or dental needs. Most important, lack of health care coverage significantly reduced the relationships between unemployment (by 26%) and underemployment (by 56%) and unmet medical or dental needs. These results indicate that lack of health insurance at least partially mediates the effects of employment problems on single mothers experiencing an unmet medical or dental need. The findings have implications for these mothers' medical and dental care access, which are discussed within the context of the recent health care reforms. [ABSTRACT FROM AUTHOR]

This study evaluated the clinical features, treatment strategies and outcomes of solid hemangioblastomas in 28 patients diagnosed with hypervascular lesions in the posterior fossa. Preoperative embolization of the feeding arteries had limited effects, with only 7 patients benefitting from it for the reduction of intraoperative hemorrhage. The tumor was completely removed in all patients, and 22 patients had a full recovery, while 6 patients, all of whom had van Hippel Lindau disease, developed recurrences. The present study demonstrated that meticulous en bloc surgical resection was the optimal treatment for solid hemangioblastomas of the posterior fossa. For large tumors, preoperative embolization was critical for preventing postoperative morbidity. Given the improvements in microsurgical techniques and the understanding of the tumor vascular pattern, total tumor removal associated with a low mortality rate could be achieved. [ABSTRACT FROM AUTHOR]

The past years have evidenced the rapid development of photochromic coordination compounds; however, the impact of coordination on the photochromic behavior of organic dyes has never been explored in the pyridinium derivative photochromic system. In this work, two new coordination compounds with a photoactive pyridinium-based inner salt, [Zn(H2O)6](PTA)·(CEbpy)2·2H2O (1, PTA = terephthalate, CEbpy = 1-carboxyethyl-4,4'-bipyridine) and [Zn(H2O)2(CEbpy)2]nBr2n·[Zn(H2O)4(PTA)]n (2), were selected as model compounds for this purpose. Compound 1 features an isolated structure, where uncoordinated photoactive CEbpy ligands connect to hexahydrated zinc ions through hydrogen bonds. Compound 2 features a 1-D chain structure with CEbpy ligands coordinating to zinc ions. Compound 1 shows faster coloration speed upon irradiation than 2, demonstrating that coordination of the electron donor in CEbpy is not in favor of photochromic behavior. Both compounds show significant photoluminescence quenching after coloration, and the intensity contrast before and after coloration for 1 is larger than that for 2. This finding will help to design and synthesize new photochromic compounds with high performance. [ABSTRACT FROM AUTHOR]

Two new isostructural coordination compounds exhibit the rare difunctional properties of both electron-transfer (ET) photochromism and ET thermochromism, which are significantly affected by halogen atoms. The thermocrystallographic studies of the same single crystal have elucidated the electron-donating nature of the halogen atoms. [ABSTRACT FROM AUTHOR]

Two novel manganese thioarsenates, {[Mn(2,2'-bipy)2(SCN)][Mn(2,2'-bipy)](AsVS4)}2 (1, 2,2'-bipy = 2,2'- bipyridine) and {[Mn(2,2'-bipy)2(SCN)]2[AsIII 2(S2)2S2]} (2), containing thiocyanate-modified Mn-2,2'-bipy complex cations were synthesized. They feature two terminal [Mn(2,2'-bipy)2(SCN)]+ complex cations bridged by a polyanion {[Mn(2,2'-bipy)]2(AsVS4)2}2- for 1 and a cyclic thioarsenate anion (AsIII2S6)2- for 2. In 2, the [AsIII2(S2)2S2]2- anion can be described as two (AsIIIS3)3- trigonal-pyramids interlinked through S-S bonds. The method to obtain new metal complex cations shown here, introducing an anionic second ligand to modify the number of coordination sites and the charges of the metal complex cations simultaneously, is different from the traditional methods, varying either the TM center or the organic ligand or employing mixed neutral organic ligands, and may open up a new route for preparing novel chalcogenidometalates. Compounds 1 and 2 exhibit wide optical gaps of 2.20 and 2.67 eV, respectively, and photoluminescence with the emission maxima occurring around 440 nm. Magnetic measurements show the presence of antiferromagnetic interactions between MnII centers in the two compounds. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to determine the prevalence of coronary angiographically evident atherosclerotic stenosis associated with myocardial bridging (MB) and to explore related risk factors of coronary artery stenosis located proximally to MB. Methods: Overall, 603 patients with MB-mural coronary arteries (MB-MCAs) diagnosed by angiography initially were enrolled in this observational study during May 2004 to May 2009. One-way ANOVA, t-test, Pearson correlation test and stepwise multiple regression analysis were performed to explore related risk factors. Results: Totally 644 MB-MCAs were examined. Prevalence of lesions located distally to MBs was significantly lower than those proximally to MBs [36 (5.9%) vs. 382 (62.4%), p<0.001]. Diastolic vessel diameters in MB segments were significantly smaller than reference segments p<0.001. Ulcer-like lesion was found in MB-MCA in 1 patient. Multivariate analysis suggested that vascular bifurcation lesions, the degree of narrowing and the number of diseased coronary vessels of non-MB-MCA arteries, age, low-density lipoprotein cholesterol (LDL-C)/high density lipoprotein cholesterol (HDL-C), male, course of diabetes, and systolic narrow rate (SNR) of MB-MCAs were positively related with the narrow degree of the first coronary artery stenosis (FCAS) located proximally to MBs (all p<0.05). Vascular bifurcation lesions, the degree of narrowing and the number of diseased coronary vessels of non-MB-MCA arteries, age, LDL-C/HDL-C, male, diabetes and dyslipidemia were positively related with the narrow degree of the most severe coronary artery stenosis(MSCAS) located proximally to MB (all p<0.05). Conclusion: The intramural and distal portions of a bridged artery are not the forbidden zone of artery atherosclerosis formation. SNR of MB-MCA may be one of the important decision factors to coronary artery stenosis located proximally to MB. [ABSTRACT FROM AUTHOR]

Photochromism of N-methyl-4,4'-bipyridinium (MQ+) salts and their metal complexes has never been reported. A series of MQ+ coordinated halozinc complexes [(MQ)ZnX3] (X = Cl (1), Br (2), I (3)) and [(MQ)ZnCl1.53I1.47]2(MQ)ZnCl1.68I1.32 (4), with better physicochemical stability than halide salts of the MQ+ cation, have been found to exhibit different photochromic behaviors. Compounds 1-3 are isostructural, but only 1 and 2 show photochromism. Introduction of partial Cl atoms to nonphotochromic compound 3 yields compound 4, which also displays photochromism. The photochromic response of 1, 2, and 4 indicates the presence of their long-lived charge separation states, which originate from X → MQ+ electron transfer according to ESR and XPS measurements. Studies on the influence of different coordinated halogen atoms demonstrate that the Cl atom may be a more suitable electron donor than Br and I atoms to design redox photochromic metal complexes. [ABSTRACT FROM AUTHOR]

Reaction of lanthanide oxides and 1H-tetrazolate-5-ethyl formate in water at 50 °C in the presence of pyridine afforded a series of lanthanide coordination polymers, {(Hpy)2[Pr4(tzf)7(H2O)11]·10H2O}n(1) and {[Ln2(tzf)3(H2O)6]·4H2O}n, where Ln = Sm (2), Eu (3), Gd (4), Tb (5), Dy (6), Hpy = protonated pyridine, and H2tzf = 1H-tetrazolate-5-formate acid. Polymer 1features a three-dimensional (3-D) anion framework built up by cross-linkage of tetrameric [Pr4(tzf)4]4멸 and tzf2−ligands, showing a six-connected primitive cubic (pcu) topology (412·63). Isomorphous polymers 2−6present a two-dimensional (2-D) neutral structure with a four-connected (4,4) topology. Four new coordination modes of the tzf2−ligand are first observed in tetrazolate-5-carboxylate complexes. The lanthanide contraction effect and coordination flexibility of tzf2−ligand play a key role in governing the formation of coordination polymers with different polymeric architectures. The photoluminescent analyses for 2, 3, 5, and 6suggest that ligand-to-Ln(III) energy transfer is efficient, especially for Eu(III) and Tb(III) ions, and the tzf2−ligand may act as a good “antenna molecule” to sensitize Ln(III) emission. The variable-temperature magnetic study shows that magnetic interactions between the Ln(III) ions in 1−6are mainly ascribed to the antiferromagnetic coupling as well as the depopulation of the Stark levels. The spin−orbit coupling parameters (λ) for Sm(III) in 2and Eu(III) in 3are 259(2) and 344(1) cm−1, respectively, based on the free-ion approximation. [ABSTRACT FROM AUTHOR]

Herein the recent experiments performed by the authors on fabricated multi-walled BN nanotubes and monoatomic BN graphene-like nanosheets are reviewed. The results are presented in several sections, namely: (i) method for high-yield synthesis of thin, defect-free BN nanotubes of only a few-layers, with external diameters below 10 nm; (ii) verification of BN nanotube piezoelectrical behavior and its electrically-induced thermal decomposition under combined resistive heating and electrical charging in a transmission electron microscope; (iii) the first direct measurements of the true tensile strength and Young's modulus of BN nanotubes, using newly developed nanotensile tests inside an electron microscope; the measured values were found to be ∼30 GPa and ∼900 GPa, respectively; and (iv) diverse kinetic processes taking place within the prepared monoatomic BN sheets (so-called 'white graphenes') affiliated with intensive knock-on B and N atom displacements under high energy electron beam irradiation in an aberration-corrected medium-voltage high-resolution transmission electron microscope. [ABSTRACT FROM AUTHOR]

Two bifunctional 1H-tetrazolate-5-carboxylate ligands with different flexibilities, H2tza (1H-tetrazolate-5-acetic acid) and H2tzf (1H-tetrazolate-5-formic acid), were employed in the construction of zinc(II) complexes in the presence/absence of secondary ligands such as 2,2′-bipy and 4,4′-bipy. Three tza coordination polymers and two tzf dinuclear complexes, namely [Zn(tza)(H2O)]n(1), [Zn3(tza)2Cl2(2,2′-bipy)2(H2O)2]n(2), [Zn2(tza)2(4,4′-bipy)]n(3), [Zn(tzf)(H2O)3]2·2H2O (4) and [Zn(tzf)(2,2′-bipy)(H2O)]2·H2O (5), were hydrothermally synthesized and structurally characterized by single-crystal X-ray diffraction. Polymer 1is a 3-D two-fold interpenetrating diamond-like network with tetranuclear [Zn(COO)]4clusters as tertiary building units (TBUs) and µ3-κN3:κO2:κO1,N1 bridging tza as linkers. Polymer 2presents a 2-D structure formed by the linkage of 1-D Zn-carboxylate [Zn(COO)]nhelical chains and µ3-κN4:κO2:κO1,N1 bridging tza. In 3, 2-D (4,4) nets are built up with dinuclear [Zn(COO)]2clusters and µ3-κN4:κO2:κO1,N1 bridging tza, which are pillared through 4,4′-bipy to gain a 3-D self-penetrating LB-1 (446108) topology. In dinuclear complexes 4and 5, two Zn(II) atoms are bridged by a tzf ligand in a µ2-κN2:κO1,N1 fashion. The results denote that tetrazolate-5-carboxylate ligands can adopt variable coordination modes in the formation of the complexes, and different Zn-carboxylate aggregates can serve as tertiary building units (TBUs). The effects of the nature of tetrazolate-5-carboxylate ligands and secondary ligands, and hydrothermal reaction conditions on the structural topologies of the obtained complexes have been investigated. The photoluminescent properties and thermal stabilities of 1–5have also been discussed. [ABSTRACT FROM AUTHOR]