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An electrochemical biomimetic sensor was developed for fast and selective detection of ascorbic acid (AA) in orange juice samples via electropolymerizing o-phenylenediamine on the surface of a dual channel screen-printed carbon electrode (SPCE), which could achieve two repetitive measurements by using the same sample drop and improve test efficiency. The square wave voltammograms and scanning electron microscopy images indicated that the many imprinted cavities had formed in the AA-imprinted poly( o-phenylenediamine) film, which acted as a selective recognition element to determine AA by means of the matched size, shape, and orientation of the functional groups between the imprinted cavities and AA molecules. The response current of the imprinted sensor was linearly related to the concentration of AA in both lower concentration regions (0.45-13.52 μM) and higher concentration regions (13.52-409.10 μM), respectively. The detection limit was 0.11 μM based on the signal to noise ratio of 3. The sensor was applied to determine AA in commercial orange juice, and the result was in good agreement with that obtained by 2,6-dichlorophenol indophenol titration method. The fabrication of the sensor was simple and timesaving (<35 min for modifying two work electrodes). Together with portability and disposability of the AA-MIP/SPCE, the proposed sensor had widely potential applications in field test and analysis. [ABSTRACT FROM AUTHOR]

Transition metal oxides are promising high-capacity anode materials for next-generation lithium-ion batteries. However, their cycle life remains a limiting factor with respect to their commercial applications. The development of transition-metal oxide anode materials with long lifespans through a facile route has become an important issue. A straightforward strategy is designed for the fabrication of a NiCo2O4 nanoplates–reduced graphene oxide sheets (NiCo2O4–RGO) composite. It displays a high reversible capacity of 816 mA h g−1 over 70 cycles with 80.1% capacity retention of the 2nd cycle and excellent rate capability. Its rate capability and cycling stability are enhanced in comparison with those of pure NiCo2O4 nanoplates. The as-obtained nanocomposite avoids the problems of dispersion and aggregation induced by cracking or pulverization of the transition-metal oxide upon cycling. The graphene or reduced graphene oxide not only works as a substrate to provide room for loading scattered grains, but also serves as a conductive network to facilitate the collection and transportation of electrons during the cycling, indirectly increasing the conductivity of NiCo2O4. [ABSTRACT FROM AUTHOR]

Abstract: NiCo2O4 is a potential lithium-ion battery (LIB) anode material that can be applied to the industrial production for commercial applications. However, the capacity and cycling stability of the LIB based on NiCo2O4 should be improved first. Herein, graphene-based NiCo2O4 nanosheet arrays directly grown on nickel foam have been successfully synthesized. This composites array shows significantly improved lithium storage properties with higher reversible capacity and better cycling stability than NiCo2O4 nanosheets. The three-dimensional graphene not only serves as a conductive network to increase the conductivity of the NiCo2O4, but also can offer effective buffering to accommodate the lithiation-induced stress which is beneficial to lithium storage and cycling stability. [Copyright &y& Elsevier]

Porous α-Fe2O3 nanospheres have been successfully prepared by a microwave-assisted hydrothermal method coupled with an annealing technique. The porous α-Fe2O3 nanosphere-based sensor presented a fast response, enhanced sensitivity and excellent selectivity towards H2S due to its intrinsic characteristics, porous structure and nanoscale size. [ABSTRACT FROM AUTHOR]

Herein, we report the synthesis of hierarchical small quantity Mo-decorated Co3O4 nanowire arrays on nickel foam substrates by a powerful two-step solution-based method. The “oriented attachment” and “self-assembly” crystal growth mechanisms are proposed to discuss the growth of the Mo-decorated Co3O4 heterostructures. This heterostructure material with a high specific surface areas provides an extraordinarily high area capacitance of 3.5 F cm−2 at a current density of 17 mA cm−2 (∼2000 F g−1 at a current density of 10 A g−1) in the initial cycles, compared with a bare Co3O4 nanowire array electrode with 2.2 F cm−2 at 17 mA cm−2 (∼1257 F g−1 at 10 A g−1), exhibiting a significant increase in the capacitance of around 60%. When the current density of the hybrid array is increased by 20 times (1.7 to 34 mA cm−2), more than 73% of the specific capacitance can be maintained, which shows a good rate performance. Such a growth approach offers a versatile technique for the design and synthesis of metal oxide hierarchical nanoarrays for electrochemical energy storage applications. [ABSTRACT FROM AUTHOR]

Abstract: This paper reported a novel sensing material of porous Ni-doped SnO2 hollow spheres with nanoheterostructures, which were synthesized by a low-cost and environment-friendly hydrothermal strategy. In the process of synthesis, long-chain polymers nickel nitrilotriacetic acid (NiNTA) were formed previously and then successfully heteroconnected with SnO2 through a series of hydrothermal reactions for the reason that nitrilotriacetic acid (NTA) could be dissolved in the aqueous solution of NaSnO3, leading to the complete change of previous morphology. The response of the sensor based on porous Ni-doped SnO2 hollow spheres is up to 59 at 100ppm ethanol and the detection limit can be dropped to 1ppm-level, which exhibits enhanced response compared with many ethanol sensors based on pure SnO2 hollow spheres. Such good performance is probably attributed to the formation of p–n junctions between NiO and SnO2, which increase the resistance of sensor and the depletion layers. [Copyright &y& Elsevier]

Owing to high theoretical capacitance, nickel cobalt alkaline carbonate (NiCoAC) has attracted wide attention in electrochemical energy storage. However, the high surface ionic resistance and low bulk intrinsic activity result in NiCo‐AC being unable to exhibit fast electronic response frequency and charge storage. Herein, via precisely controlling gradient S‐doping, NiCo‐AC nanowire is in situ converted into core‐shell bimetallic oxysulfide (NiCo─O─S), with interior particularly presenting a granular due to the contraction of bulk structure, achieving the synergistic modification of surface and bulk. Specifically, owing to the lower band gap energy of metal sulfides, the derived shell optimizes OH− adsorption center from Ni to Ni─Co─Ni sites with higher binding energy, and the granular core facilitates further ion diffusion with enhanced charge accumulation. Hence, NiCo─O─S reflect higher redox activity than that of nickel‐cobalt sulfide (NiCo─S) and NiCo‐AC, with an ultrahigh capacitance of 3,298 F g−1 at 1 A g−1. The as‐fabricated supercapacitors display an outstanding energy density of 131 Wh kg−1 at 800 W kg−1 and present high capacitance retention of 98.5% and coulomb efficiency of 93.2％ under 12 000 charge‐discharge cycles. This study reflects a new insight into activating the intrinsic activity of nanomaterials to further develop high‐rate and stable electrodes. [ABSTRACT FROM AUTHOR]

Sodium metal batteries (SMBs) are the ultimate choice for high‐energy density sodium‐based batteries. However, their practicality is still constrained by the uncontrolled side reactions and unstable solid electrolyte interface (SEI) between the electrolyte and Na‐metal anode. Herein, a hetero‐salt additive (Lithium difluorophosphate, LiDFP) strategy is proposed to optimize the solvation structure of pseudo gel‐polymer electrolyte (pGPE) and construct robust SEI on Na metal anode, thereby enhancing Na+ deposition/stripping kinetics. Detailed characterization reveals that Li+ with lower binding energy to solvent molecules can steal solvent molecules from Na+ coordination environment, and then push anions to further coordinate with Na+. The formed anion‐enriched solvation structure can assist to restrain side reactions and form a robust inorganics‐dominated SEI on Na metal anode. Consequently, such optimization effectively realizes outstanding electrochemical performance of the cells under wide operation temperature (−20 to 70 °C) and prolongs cycling life (1900 h) of Na plating/stripping. Furthermore, paired with commercial NaNi1/3Fe1/3Mn1/3O2 (NFM) cathode and hard carbon (HC) anode, the pouch cell using pGPE+0.5%LiDFP delivers a high‐capacity retention of 87.5% at 45 °C after 250 cycles. It is believed that this work affords emerging chances for the rational electrolyte design of stable wide‐temperate SIBs. [ABSTRACT FROM AUTHOR]

The plating/stripping behavior of Zn ions on the Zn anode, driven by an electric field, is a key process in determining the performance of aqueous zinc ion batteries (AZIBs). Process‐induced unevenness of commercial Zn foils results in poor reversibility of Zn anodes. Herein, a self‐healing dynamic anode/electrolyte interface is constructed by incorporating hydroxyl‐rich alcohols with high charge density and zincophilicity into the original electrolyte. These alcohols selectively anchor on electron‐poor sites in the charging state, inducing domain‐limited deposition of Zn2+ to achieve a dense, uniform, and flat deposition state. As a result, a durable Zn anode with excellent electrochemical reversibility can be realized in practical cycling (average Coulombic efficiency of 99.5%). Even under deep plating/stripping conditions (5 mA cm−2 and 5mAh cm−2), the modified electrolyte exhibits a remarkable repair effect on corroded Zn anodes that have been cycled in base electrolyte, extending the lifespan to over 1,020 h. This represents a 15.6‐fold enhancement in lifespan compared to recycling in the base electrolyte. This strategy for electrolyte additive directly influences the design of ultra‐long‐life AZIBs and provides concrete concepts for the recovery of zinc anodes. [ABSTRACT FROM AUTHOR]

We have successfully observed the development of three-dimensional (3D) face-centered-cubic ZnSnO3 into two-dimensional (2D) orthorhombic ZnSnO3 nanosheets, which is the first observation of 2D ZnSnO3 nanostructures to date. The synthesis from 3D to 2D nanostructures is realized by the dual-hydrolysis-assisted liquid precipitation reaction and subsequent hydrothermal treatment. The time-dependent morphology indicates the transformation via a ‘dissolution–recrystallization’ mechanism, accompanied by a ‘further growth’ process. Furthermore, the 2D ZnSnO3 nanosheets consist of smaller sized nanoflakes. This further increases the special specific surface area and facilitates their application in gas sensing. The 2D ZnSnO3 nanosheets exhibit excellent gas sensing properties, especially through their ultra-fast response and recovery. When exposed to ethanol and acetone, the response rate is as fast as 0.26 s and 0.18 s, respectively, and the concentration limit can reach as low as 50 ppb of ethanol. All these results are much better than those reported so far. Our experimental results indicate an efficient approach to realize high-performance gas sensors. [ABSTRACT FROM AUTHOR]

The commercial electrolytes exhibit subpar performance under low temperature and high voltage, severely limiting the application of lithium-ion batteries (LIBs) for extreme temperature and high energy density. As a groundbreaking advancement, the regulation of Li+ solvation structure was adopted and highly concentrated in this work, obtaining an improved electrolyte with excellent low-temperature and high-voltage performance. The electrolyte exhibited outstanding oxidation potential of 5.25 V and high ionic conductivity, maintaining transparency liquid even at −60 °C. Notably, the NCM811||Li cell exhibited high initial capacity (71.41 % of that at room temperature) at −40 °C 0.2C, with almost no capacity decay after 50 cycles. Impressively, the as-assembled NCM811||Graphite pouch battery (2.5 Ah) showed an initial capacity of 2.07 Ah at 0.1C under −30 °C, with an excellent capacity retention ratio of 84.53 % after 50 cycles. This work points out a promising approach for the practical application of high-voltage LIBs at low temperature. [Display omitted] • Through regulating the highly concentrated solvation structure, the performance of electrolyte at high voltage and low temperature was improved. • The LHCE exhibits high ionic conductivity and advanced electrochemical window upper limit. • Employing this LHCE in the NCM811||Li cell (2.8–4.6 V) can endow the battery with a high specific capacity at −40 °C.. • The as-assembled NCM811||Graphite battery (2.5 Ah) showed an excellent charging and discharging performance at −30 °C. [ABSTRACT FROM AUTHOR]

Objective: To investigate the application of cavernosum reduction technology in glanuloplasty during the repair of moderate-severe hypospadias and evaluate the effectiveness., Methods: The clinical data of 192 patients with moderate-severe hypospadias between November 2015 and May 2017 were retrospectively analyzed. Among them, 103 patients were treated with the cavernosum reduction technology in glanuloplasty during the repair (observation group), 88 patients were treated with repair and glanuloplasty without the cavernosum reduction technology (control group). There was no significant difference in maximum transverse diameter of glans and the height of glans between 2 groups ( t =1.652, P =0.152; t =1.653, P =0.077). The length of reconstructed urethra, complications (e.g. glans dehiscence and fistula), and the maximum flow rate at 3 months after operation in 2 groups were recorded., Results: The length of reconstructed urethra were (35.51±7.79) mm in observation group and (32.17±6.37) mm in control group. In observation group, the meatus location after the correction of chordee was proximal in 24 cases and scrotum-perineum in 79 cases. In control group, the meatus location after the correction of chordee was proximal in 21 cases and scrotum-perineum in 67 cases. There was no significant difference in the meatus location between 2 groups ( χ 2 =0.008， P =0.920). All patients were followed up 6-12 months after operation (mean, 9 months). There were 3 cases of urethral fistula, 2 cases of glans dehiscence, and 3 cases of urethral orifice stricture in observation group, with the incidence of complications of 7.8%. There were 7 cases of urethral fistula, 3 cases of glans dehiscence, and 4 cases of urethral orifice stricture in control group, with the incidence of complications of 15.9%. There was a significant difference in the incidence of complications between 2 groups ( χ 2 =4.027, P =0.040). The appearance of the penis was satisfactory, and the urethral orifice was fissured, which was close to the appearance of the normal urethral orifice. At 3 months after operation, the maximal flow rates were (6.23 ± 0.54) mL/s in observation group and (5.44±0.92) mL/s in control group. There was significant difference in the maximum flow rate between 2 groups ( t =1.653, P =0.000)., Conclusion: Cavernosum reduction technology being applied in the repair of moderate-severe hypospadias can reduce the probability of glans dehiscence, urethral fistula, urethrostenosis, and other postoperative complications, and improve the success and satisfaction of surgery.

Objective: To explore the indication and effectiveness of urogenital sinus surgery in feminizing genitoplasty of disorder of sex development (DSD)., Methods: A retrospective analysis was made on clinical data from 22 patients with DSD who underwent one stage feminizing genitoplasty between October 2010 and December 2015. The patients' age ranged from 1 year and 2 months to 21 years, with the median age of 2 years and 1 month. According to the Prader classification criteria, the appearance of vulvas were rated as grade Ⅰ in 7 cases, grade Ⅱ in 6 cases, grade Ⅲ in 8 cases, and grade Ⅳ in 1 case. Cystoscopy was applied before feminizing genitoplasty in all patients. Low confluence of vagina and urethra was found in 19 patients, while high confluence was found in 3 patients. The mean length of urogenital sinus was 1.6 cm (range, 0.5-3.0 cm). The mean length of water-filled vagina was 4.4 cm (range, 3.5-5.5 cm). Cervix was detected at the end of vagina in 16 patients, meanwhile absence of cervix was detected in 6 patients. The same procedures of clitoroplasty and labioplasty were used in all patients. Three procedures of urogenital sinus surgery were applied, as the "cut-back" vaginoplasty in 6 patients, the "flap" vaginoplasty in 11 patients, and the partial urogenital sinus mobilization (PUM) in 5 patients., Results: All procedures were completed successfully and the incisions healed by stage Ⅰ. All patients were followed up 12-74 months, with the average of 30.5 months. The outcome of appearance evaluation was excellent in 13 patients (59.1%), good in 6 patients (27.3%), and poor in 3 patients (13.6%). Urinary incontinence, post-void residual, urinary infection, and urethrovaginal fistula were not found in 17 toilet trained patients., Conclusion: Urogenital sinus surgery is the most critical step in feminizing genitoplasty of DSD. It can be finished in one stage procedure with clitoroplasty and labioplasty before puberty. If thoroughly evaluation before surgery is completed and the principle of different procedures is handled, the outcome will be satisfactory.

In this study, we developed a new nanoparticulate system for acetylated starch nanocrystals (ASN) using broken rice. ASN with different degrees of substitution (DS) of 0.04, 0.08 and 0.14 were prepared using acetic anhydride as acetylating agent through reaction with starch nanocrystals (SN). The resulting ASN were investigated for the capability to load and release doxorubicin hydrochloride (DOX), and the antitumor activities of DOX-loaded SN and DOX-loaded ASN were evaluated as potential drug delivery systems for cancer therapy. Cellular uptake and cytotoxicity of nanocrystals and the DOX-loaded nanocrystals were investigated using fluorescence microscopy and a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) (MTT) assay. Compared with acetylated starches (AS) and native starches (NS), ASN with DS 0.14 loaded up to 6.07% of DOX with a higher loading efficiency of 91.1% and had steadier drug-release rates. Toxicity analysis using the rat hepatocytes model suggested that ASN was biocompatible and could be used for drug delivery. Furthermore, ASN were taken up by cancer cells in vitro and significantly enhanced the cytotoxicity of DOX against HeLa human cervical carcinoma cells. The IC50 value of DOX-loaded ASN-DS 0.14 was 3.8μg/mL for 24h of treatment, which was significantly lower than that of free DOX (21μg/mL). These results indicate that the prepared ASN using broken rice is a promising vehicle for the controlled delivery of DOX for cancer therapy., (Copyright © 2016 Elsevier B.V. All rights reserved.)

Objective: ?To explore the short-term effectiveness of hypospadias repairs with free inner prepuce tube., Methods: ?Forty-two males with hypospadias were repaired with free inner prepuce tube between May and October 2015. The age ranged from 1 year and 1 month to 28 years and 2 months with a median of 2 years and 9 months. Initial operation for hypospadias was performed in 41 cases and re-operation in 1 case of chordee after 16 months of hypospadias repair. There were 36 cases of hypospadias ( 6 cases of proximal penile type, 1 case of penile scrotal type, 26 cases of scrotal type, and 3 cases of perineal type) and 6 cases of type Ⅳ chordee according to Donnahoo classification criteria., Results: ?The length of reconstructed urethra was 2.0-5.5 cm (mean, 3.6 cm). The patients were followed up 6-10 months (mean, 8 months). Urinary fistulae was noted in 10 patients, which healed spontaneously in 5 cases within 3 months after surgery, and was cured after repair in 5 cases. Urethral stenosis occurred in 4 cases (2 external orifice stricture and 2 distal urethral stricture) and urethral incision was performed. Wound infection was noted in 3 cases, 2 of them needed further surgery for a permanent fistula. Skin ischemic necrosis was found in 3 cases, 1 of them had infection and fistula, and needed further surgical repair. Diverticulum of scrotum developed in 1 case. Ten patients need re-operation, and the success rate was 76.2% (32/42). At 3 months after surgery, the HOSE score ranged from 11 to 16 (mean, 14.7). The maximum urinary flow rate was 1.9-28.4 mL/s (mean, 10.5 mL/s) in 22 cases of outpatient at 3 months after surgery., Conclusions: ?Free inner prepuce tube can survive and play a role of normal neourethra. The short-term effectiveness has shown a relatively high complication rate and suggests this procedure should be carefully applied.

Objective: To explore the surgical outcome of Duckett urethroplasty-urethrotomy for staged hypospadias repair., Methods: Fifty-three patients with hypospadias were treated by 2 stages between August 2013 and September 2014. The age ranged from 10 months to 24 years and 3 months (median, 1 year and 10 months). There were 5 cases of proximal penile type, 2 cases of penoscrotal type, 36 cases of scrotal type, and 10 cases of perineal type. Urethroplasty was performed with tubed transverse preputial island flap only in 27 cases or combined with urethral plate in the other 26 cases, thus a urethrocutaneous fistula was intentionally created; stage II fistula repair was carried out at 1 year after stage I repair., Results: The length of the new urethra ranged from 2 to 8 cm with an average of 3.6 cm. The patients were followed up 5-17 months with an average of 8 months after stage II repair. After stage I repair, urethral fistula was noted at other site in 3 cases, skin necrosis in 1 case, glandular stricture in 2 cases, cicatric curvature in 1 case, and position and morphology of urethral orifice not ideal in 4 cases. After stage II repair, urethral fistula was noted in 2 cases, mild urethral diverticulum in 2 cases, and stricture at temporary repair site in 1 case. HOSE score was 12-16 at 3 months after stage II repair (mean, 14.5). At 3-14 months after stage II repair, the maximum flow rate ranged from 3.9 to 22.7 mL/s with an average of 8.6 mL/s., Conclusions: Duckett urethroplasty-urethrotomy can be used as staged repair for primary treatment of hypospadias because of high safety, low complication incidence, and satisfactory appearance.

α-Fe(2)O(3) nanochains have been successfully synthesized via an ammonium acetate-based ionothermal synthetic route. When detecting low-ppm-level H(2)S gas, the nanochain sensor displayes high sensitivity due to its unique structure and smaller size.