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• Bimetallic CoZnMOF and borate-irradiation treatment are developed to improve the kinetics of BiVO 4. • CoZnMOF/B-BVO achieves an excellent photocurrent density of 4.27 mA/cm2. • The mechanism of oxidation state modulation of CoMOF with Zn is explored. Metal-organic frameworks (MOFs) have been proved to be outstanding catalysts for oxygen evolution reaction (OER). When compared to monometallic MOFs, it's demonstrated that bimetallic MOFs have higher activity and stability. However, the coupling effect of the two metallic ions in bimetallic MOFs is unclear. To clarify the mechanism, bimetallic CoZn-MOFs with OER-inert Zn species are coated on BiVO 4 photoanodes. Results show that the oxidation state of Co is improved through the addition of Zn. Combining with borate-irradiation treatment, the CoZnMOF/B-BVO achieves a photocurrent density of 4.27 mA/cm2, which is 3.16 times that of the BVO electrode. Furthermore, the onset potential is negatively shifted by 253 mV, the surface charge injection efficiency is 91% (vs 43.5%, BVO), and the bulk charge separation efficiency reaches 88.2% (vs 51.3%, BVO). The photocurrent of CoZnMOF/B-BVO retains 90% after 10 h test. Oxidation state modulation of MOFs with the second metal is an effective strategy to improve MOFs' activity. [Display omitted] [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) urea splitting is of great significance for urea wastewater remediation and hydrogen production with low energy consumption simultaneously. Nickel hydroxides as electrocatalysts have been widely investigated for urea electrolysis. However, it is an open question how to synthesize highly catalytic Ni(OH)2 for the PEC urea splitting. Herein, we take advantage of the instability of metal–organic frameworks (MOFs) to perform an in situ synthesis of Ni(OH)2 catalysts on the surface of TiO2 nanorod arrays. This transformed Ni(OH)2 (T-Ni(OH)2) possesses a superior PEC catalytic activity for water/urea splitting in comparison to the Ni(OH)2 prepared by the impregnation method. The in situ transition of a Ni-MOF is accomplished through an electrochemical treatment under AM1.5G illumination in a KOH-and-urea mixed electrolyte. The specific transition mechanism of Ni-MOFs is the substitution of ligands with OH− in a 1 M KOH electrolyte and the successive phase transition. The T-Ni(OH)2@TiO2 photoanode delivers a high photocurrent density of 1.22 mA cm−2 at 1.23 VRHE, which is 4.7 times that of Ni(OH)2@TiO2 prepared with the impregnation method. The onset potential of T-Ni(OH)2@TiO2 is negatively shifted by 118 mV in comparison to TiO2. Moreover, the decline of photocurrent during the continuous test can be recovered after the electrochemical and light treatments. [ABSTRACT FROM AUTHOR]

Limited by meteorological conditions, airspace, complex terrain and other factors, airborne millimeter-wave InSAR will inevitably face the situation of no control point layout when acquiring terrain data in the difficult mapping areas in Southwest China, which increases the difficulty of subsequent data processing. Moreover, the layout of control points in difficult mapping areas consumes a lot of manpower and time, which is not suitable for large-scale high-precision topographic mapping. To solve these problems, this paper proposes an automatic extraction of tie-points and interferometric calibration technology based on tie-points. This technology develops the automatic extraction algorithm of tie-points based on SAR + SIFT + RANSAC to obtain evenly distributed tie-points of adjacent images, and uses the evenly distributed tie-points as real known points to recalibrate the interference parameters, then carries out elevation transfer and elevation inversion through the tie-points of overlapping areas, thus realizing high-precision mapping without control points for airborne millimeter-wave InSAR. This paper uses measured data to verify the technology, and compares it with the areas with control points and marking points. The comparison results of elevation accuracy prove the feasibility and effectiveness of this method. This paper also discusses the difficulties in the treatment of typical areas, such as water areas, urban areas and mountain areas, and gives reasonable solutions that have good engineering application value. [ABSTRACT FROM AUTHOR]

Tannin-modified phenolic resin has the characteristics of a high molecular weight, high space resistance, high viscosity, and short shelf life. Therefore, it is still very difficult to use concentrated tannins without pretreatment. To utilize the benefits of condensed tannins, the depolymerization of condensed tannins was carried out in a mixed aqueous solution of sodium hydroxide and urea. The effects of different NaOH/urea ratios on depolymerization were investigated. It was found that tannin treatment was optimized when NaOH/urea/water = 12:7:81 (0.2 mol:0.175 mol:4.5 mol). Gel permeation chromatography (GPC) showed that the weight-average molecular weight of the condensed tannins decreased from 1725 Da to 704 Da–1523 Da and 327 Da. The changes in the molecular structure of the depolymerized products were detected by MALDI-TOF-MS, 13C nuclear magnetic resonance, and infrared spectroscopy. The results showed that the average degree of polymerization of tannin decreased from 7 to 2. The decrease in the degree of polymerization was mainly due to the breaking of C-4 and C-8 chemical bonds. Some ether bonds were broken, which reduced the molecular weight of the tannin and gave it a more uniform distribution in water. In addition, tannin-modified phenolic resin (DTPF) was prepared by the copolycondensation of phenol, tannin depolymerization products, and formaldehyde under alkaline conditions. The molecular structure and properties of DTPF were studied by 13C NMR, FTIR, DSC, and TG. The results revealed that, compared with untreated tannin-modified phenolic resin (TPF), DTPF resin had lower formaldehyde emission (0.19 mg/L), better thermal stability, and higher bonding strength (1.19 MPa), according to GB/T 17657-2013. It is important to note that this inexpensive and environmentally friendly catalyst can be used as a raw material for the synthesis process; the degradation products do not need to be recovered and purified, thus avoiding the dehydration and purification of the waste liquor, which is safer for the environment. Image 1 [ABSTRACT FROM AUTHOR]

Phenolic foam composites (PFs) are of substantial interest due to their uniform closed-cell structure, low thermal conductivity, and good thermal insulation performance. However, their disadvantages of a high pulverization rate and poor mechanical properties restrict their application in building exterior insulation. Therefore, the toughening of these composites is necessary. In this paper, poplar fiber was treated with an acetylation reagent, and the acetylated fiber was used to prepare modified phenolic foams (FTPFs); this successfully solved the phenomenon of the destruction of the foam structure due to the agglomeration of poplar fiber in the resin substrate. The foam composites were comprehensively evaluated via the characterization of their chemical structures, surface morphologies, mechanical properties, thermal conductivities, and flame retardant properties. It was found that the compressive strength and compressive modulus of FTPF-5% respectively increased by 28.5% and 37.9% as compared with those of PF. The pulverization ratio was reduced by 32.3%, and the thermal insulation performance and flame retardant performance (LOI) were improved. Compared with other toughening methods for phenolic foam composites, the phenolic foam composites modified with surface-compatibilized poplar fiber offer a novel strategy for the value-added utilization of woody fiber, and improve the toughness and industrial viability of phenolic foam. [ABSTRACT FROM AUTHOR]

Pseudocapacitance is mainly contributed by fast surface‐controlled reactions. However, the effect of nanostructures on the capacitive behaviour has not been systematically studied yet. In this work, we synthesize different Co3O4 nanostructures with the same crystal structure and exposed clean crystal planes that include 1D nanowire, 2D nanosheet, 3D rambutan‐like and hierarchical structures, ranging from low to high dimensions. It is discovered the specific capacitance of Co3O4 materials follows the order of 1D nanowire > hierarchical structure > 2D nanosheet > 3D rambutan‐like structure while the electron transfer resistance is 1D nanowire < 2D nanosheet < hierarchical structure < 3D rambutan‐like structure. Under the same electrochemistry, results suggest the pseudocapacitance is not simply dependent on the surface area offered by the nanostructure, but relies on the conductivity, accessibility, diffusion rate and reactivity of the electrode. 1D nanostructure can render the highest reactant accessibility, fastest electron transfer and largest diffusion rate, thus achieving the highest specific pseudocapacitance. [ABSTRACT FROM AUTHOR]

Wood dyeing usually requires a large concentration of metal solution, which when released to the atmosphere as waste liquid, causes pollution. In this study, a metal-organic framework (MOF) with micron-size structure was in-situ grown on a wood surface as a template and precursor for a layered double hydroxide (LDH). The LDH had a nanoscale structure and was generated on the wood surface from ultra-low concentration NiCl 2 solution. The generation was based on a hydrolytically induced exchange process between the MOF and hydroxide ions. The results of following this procedure showed that petal-like Co/Ni-LDH with micro-nano composite structure was formed on the wood surface. Due to the LDH, a uniform light green color was formed on the wood surface at a reaction temperature and time of 60 ℃ in 34 min, respectively. To improve the hydrophobicity of the LDH layer, a long chain alkyl with low surface energy was introduced into the lamellae from a sodium stearate solution, constructing a superhydrophobic layer on the wood surface. The modified wood surface showed excellent UV light aging and water resistances. Moreover, Ni2+ was replaced with Mn2+, Fe3+, Cu2+, and Zn2+ ions and dark brown, yellow, blue, and white colors, respectively, were formed on wood. The present method is also suitable for other wood. Wood surface color adjusted by LDH uses low concentration of metal salt solution and proved to be a mild and green wood color toning method. [Display omitted] • The study proposed a mild method for wood color adjustment. • LDH was generated by hydrolysis induction using MOF as sacrificial template. • Ultra-low concentration solution of metallic salts (0.016 mol/L) was needed. • Surfaces were made superhydrophobic. • This method is applicable to a variety of transition metal salt solution and wood. [ABSTRACT FROM AUTHOR]

[Display omitted] • ZnO layer is coated on the surface of CuBi 2 O 4 /CuO heterojunction photocathode. • Twofold photocurrent has been achieved with the CuBi 2 O 4 /CuO/ZnO photocathode. • PEC stability of CuBi 2 O 4 /CuO has been efficiently prolonged to 12 h level. CuBi 2 O 4 has received a lot of attention because of its suitable bandgap and positive onset potential. However, the reported photocurrent density based on the CuBi 2 O 4 photocathode is still far less than its theoretical value. Herein, a layer of amorphous ZnO is coated on the surface of CuBi 2 O 4 /CuO heterojunction photocathodes by an electrodeposition method. The photocurrent density achieved by CuBi 2 O 4 /CuO/ZnO is 2.1 times that of CuBi 2 O 4 /CuO, from 0.56 mA cm−2 to 1.18 mA cm−2 at 0.2 V RHE in 0.5 M Na 2 SO 4. Additionally, after 12 h stability testing, the photocurrent retention rate of CuBi 2 O 4 /CuO photocathode with a ZnO protective layer can be maintained at 84%, while only 58% photocurrent retention can be obtained with the bare photocathode. The performance improvement can be attributed to the fact that the electrodeposited amorphous ZnO overlayer provides more active sites, reduces the surface charge transfer resistance, and protects the unstable CuBi 2 O 4 /CuO photocathode. This work manifests a ZnO overlayer prepared by the electrodeposition approach is one of efficient strategies to fabricate one durable and high-performance CuBi 2 O 4 based photocathodes. [ABSTRACT FROM AUTHOR]

In this study, we examined the ultraviolet (UV) light-induced degradation of Orange IV (O-IV) in an aqueous solution containing nitrite (NO 2 -). The observed pseudo-first-order rate constants of O-IV (k obs) degradation were assessed based on the effects of different influencing factors, including the initial concentration of O-IV, light intensity, temperature, pH, NO 2 - concentration, and inorganic anions. The results showed that O-IV was significantly removed with a k obs of 0.05268 min-1 in the UV/ NO 2 - system. Quenching experiments and electron paramagnetic resonance (EPR) spectroscopy determined the possible active species in the UV/ NO 2 - system, including hydroxyl radical (̇OH) and singlet oxygen (1O 2). k obs decreased with an increase in the initial concentration of O-IV, possibly because the number of ˙OH produced by NO 2 - was not sufficient to remove all the dye molecules. k obs increased with an increase in light intensity and NO 2 - concentration, and the degradation of O-IV under acidic or alkaline conditions was inhibited. The most influential inorganic anions were carbonate ions ( CO 3 2 -) , which reacted with ˙OH and rendered photochemical reactions less efficient. Additionally, a possible photodegradation mechanism of O-IV was proposed using liquid chromatography-mass spectrometry (LC-MS) analysis. Finally, the response surface methodology (RSM) was performed, the reaction parameters were optimized, the RSM model (R2 =0.9746) was constructed, and the optimal experimental conditions were obtained using the model with an NO 2 − concentration of 12.91 mmol/L, pH of 7, and light intensity of 32 W. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Thirty-five novel isoxazoloquinone derivatives were synthesized and most of them showed decent antipsoriatic activity in vitro. • B20 inhibited STAT3 signaling pathways by binding to the SH2 domain of STAT3. • B20 inhibited the production of STAT3-downstream pro-inflammatory factor IL-17A. • B20 showed remarkable antipsoriatic activity in a mice model. Psoriasis is a troublesome scaling skin disease with no high-effective medication available by far. Signal transducer and activator of transcription 3 (STAT3) has recently been revealed as a crucial player in the pathogenesis and progression of psoriasis and emerged as an intriguing antipsoriatic drug target. Naturally occurring lapachol and its quinone analogs had been discovered as effective STAT3 inhibitors, however, their antipsoriatic effects are not well investigated. Previously, we have reported a series of isothiazoloquinone lapachol derivatives. Here, the antipsoriastic potentials of these isothiazoloquinones were investigated and, in addition, 35 novel isoxazoloquinone derivatives were prepared and studied for their anti-psoriasis properties. Among them, the most potent antipsoriatic compound B20 determined by in vitro test on HaCaT cells could directly bind to STAT3, reduce STAT3 level and inhibit STAT3 nuclear translocation. In vivo studies showed that topical application of B20 could effectively alleviate IMQ-induced psoriasis in mice with no obvious side effects. In addition, B20 inhibited the production of interleukin 17 (IL-17A), a STAT3-downstream cytokine essential for the progression of psoriasis, both in vitro and in vivo. Thus, isoxazoloquinone B20 is a potent STAT3-targeting antipsoriatic agent worth of further investigation. [ABSTRACT FROM AUTHOR]

Low charge separation efficiency (η sep) of TiO 2 impedes its applications of photoelectrochemical (PEC) water splitting. A positive potential pretreatment approach has been developed to construct a surface polarization with −OH groups at a potential of 1.48 V RHE. When the pretreatment time of 6 h is used, the η sep and photocurrent density (J ph) reach up to 54 % (vs. 24 %, TiO 2) and 0.92 mA cm−2 (vs. 0.32 mA cm−2, TiO 2) under AM 1.5 G illumination, respectively. The photovoltage can be increased from 0.17 V to 0.52 V. When the pretreatment time is extended to 22 h, a higher J ph of 1.57 mA cm−2 and η sep of 87 % can be obtained. Furthermore, the positive potential pretreated TiO 2 possesses excellent PEC stability. The PEC improvements can be attributed to the surface polarization with the −OH groups and favorable surface states of Ti-OH, but not to the formation of Ti3+ or oxygen vacancies. [Display omitted] • A positive potential pretreatment method is developed to construct TiO 2 surface polarization with −OH groups. • A higher photocurrent and charge separation efficiency of 1.57 mA cm−2 and 87 % are obtained, respectively. • Positive potential pretreated TiO 2 shows an excellent stability, which greatly vary from the electrochemical reduced TiO 2. [ABSTRACT FROM AUTHOR]

In order to explore the effect of amount of additional water on physicochemical properties of vanadium phosphate (VPO) materials prepared in a Deep Eutectic Mixture (DES), various supernumerary amount of water (H 2 O: DES ​= ​0, 0.13, 0.26, 0.39, 0.52, mass ratio) was added during synthesis. The result showed that adding appropriate quantity of water in preparation process was benefit to forming pore space framework and obtaining higher BET surface area, however, excessive quantities of water would destroy aperturestructure, seriously resulting in atresia. In addition, as the accessorial water content in a DES augmented, crystallite size of VPO materials increased and phase of that changed from amorphous to crystalline state. More than that crystalline phase types also altered. Further, the morphology of products varied from amorphous blocks to nano-particles and then to nano-sheets, finally to cuboids. What's more, VPO catalysts corresponded to reaction conversions were pretty much the same, but reaction selectivity existed a great difference under the same reaction condition. It was obvious that water played an important role in ionothermal synthesis, which may inspire us to regulate the morphology, pore space framework, crystallite size and catalytic performance of VPO materials by controlling moisture content of DES in the future. It was obvious that water played an important role in ionothermal synthesis, which may inspire us to regulate the morphology, pore space framework, crystallite size and catalytic performance of VPO materials by controlling moisture content of DES in the future. [Display omitted] • VPOs with diverse structures and performances were prepared in DES. • A key factor in synthesis is moisture content of DES. [ABSTRACT FROM AUTHOR]

This study was designed to investigate the relationship of insulin resistance (IR) and cellular immune abnormalities associated with women with recurrent pregnancy loss (RPL). Women with RPL were divided into two groups according to their homeostasis model assessment for IR (HOMA-IR) scores. The IR group received metformin approximately 3 months before pregnancy. The percentage of lymphocyte subsets and other blood biochemical indices were tested. The HOMA-IR and fasting serum insulin levels were related to the percentage of lymphocyte subsets. The women with RPL had higher CD3+and CD3+CD4+cell levels while CD56+CD16+cell levels were lower. A higher likelihood of cellular immune abnormalities was observed. Women with normal lymphocyte subsets had normal pregnancy outcomes. Metformin significantly downregulated CD3+and CD3+CD4+cells and improved pregnancy outcomes. IR was associated with cellular immune abnormalities in RPL. The data suggests that metformin affected the immune/inflammatory response, which may regulate the cellular immune balance and improve pregnancy outcomes. AbbreviationsRPL: recurrent pregnancy loss; IR insulin resistance; HOMA-IR: homeostasis model assessment for IR [ABSTRACT FROM AUTHOR]

• The GCE sensor based on MWCNTs-BMIMPF6-Nafion detected Cu (Ⅱ) ions. • Nafion can significantly improve the easy falling of the modification layer. • The fabricated sensor has excellent anti-interference and stability. • The fabricated sensor determined Cu (Ⅱ) ions in actual food samples. Due to a small amount of Cu (Ⅱ) ions being beneficial and too much being harmful, it is necessary to establish a rapid and direct detection method. Herein, we reported a platform based on multiwalled carbon nanotubes (MWCNTs), 1-butyl-3-methylimidazolium hexafluorophosphate (BMIMPF6), and Nafion solution-modified glassy carbon electrode (GCE) for the direct electrochemical detection of Cu (II) ions. We used differential pulse anodic stripping voltammetry, including the electrodeposition of Cu (Ⅱ) ions on the modified GCE and subsequent anodic stripping. Under the optimum conditions, the linear range was 20 μg·L−1 ∼ 950 μg·L−1, the limit of detection (LOD) was 16 μg·L−1, and the limit of quantification (LOQ) was 54 μg·L−1 for Cu (II). We realized the quantitative detection of Cu (Ⅱ) ions in juice and tea beverage without tedious pretreatment. The result showed that the sensor had good anti-interference and practicability for actual food samples. [ABSTRACT FROM AUTHOR]

It is vital to effectively retain the high latent heat of phase change material (PCM) when it is encapsulated in package matrix. Natural Wood has been considered as a potential matrix for PCM package as its micro-pore and nano-pore structures and rich in active groups. However, the influence of the wood pore structure on the latent heat of PCM is still unclear. In this study, paraffin wax was encapsulated with delignified balsa wood, and the influence of the pore structure of delignified balsa wood on the latent heat of PCM was investigated. The obtained results showed that the melting latent heat of the wood-based phase change material (WCPCM) with delignification treatment increased from 135.7 J/g to 175.1 J/g. This was attributed to the lower effect of the spatial confinement on the cell wall with the opening of pits and the improvement of permeability, due to the increase of the number of pores that are larger than 10 nm. The pores that are smaller than 10 nm on the cell wall were closed due to hydrogen bonding, which caused the shrinking of the wood cell wall and the increase of porosity. A superhydrophobic surface with photothermal function was constructed on WCPCM by spraying polydimethylsiloxane (PDMS) and depositing candle soot (CS). The composites can be heated from room temperature to 64.9 °C within 150 s under simulated sunlight. The efficiency of the light-thermal conversion is 87.9%. PDMS acted as an intermediate bridge to increase the stability of CS coating and gave a self-cleaning ability to the photothermal conversion coating. The composites with photothermal and self-cleaning functional coat can be used outdoor for the energy conservation of buildings. [Display omitted] • The effect mechanism of the pore size in wood on PCM was revealed. • The latent heat of PW-Wood is 29% higher than that of LWP due to the change of pores. • A coating with photothermal and self-cleaning based on CS and PDMS was prepared. • The PDMS acts as a bridge improving mechanical durability of the coating. • The photo-thermal conversion efficiency of CS-Wood is 87.9%. [ABSTRACT FROM AUTHOR]

Abstract: Objective: To examine sleep patterns and influencing factors (age, gender, Tanner Stage, weekday vs. weekend, and pre-sleep activity) among rural Chinese adolescents. Methods: This is a prospective study among 621 adolescents aged 11–20 years (341 males) using both a questionnaire and sleep diary to obtain bedtime, wake-up time, sleep latency, and total sleep time (TST). Results: The median TST was 8.6h on weekdays and 9.4h on weekends. Despite absence of late night social pressure and computers, a U-shaped TST pattern was observed across age and Tanner Stage, with a nadir around age 15–16 years or Tanner IV. Bedtimes became progressively later with age and Tanner Stage, while wake-up time was considerably earlier for school students or up to Tanner IV. Later wake-up times and longer TST on weekends were seen in school students, but not in non-school adolescents (>17 years). Pre-sleep activity, like reading or studying, was related to later bedtime, earlier wake-up time, and shorter TST in both genders. Conclusions: Age, Tanner Stage, and pre-sleep activity affected sleep patterns in this sample of rural Chinese adolescents. Later bedtime coupled with earlier wake-up time associated with academic demand appear to be important contributors to sleep loss among school students. [Copyright &y& Elsevier]

Elevated BMI is a known risk factor for metabolic syndrome (MS). Few studies have examined the joint association of BMI and body composition with the risk of MS. Our study investigated individual thresholds of BMI and body composition for an increased risk of MS and the joint association of BMI and body composition with the risk of MS in Chinese women. This is a cross-sectional analysis of 3,734 rural Chinese women aged 20-39 years. Body composition was assessed by DEXA, including measures of percent body fat (%BF) and proportion of trunk fat to total body fat (%TF). Graphic plots were used to explore BMI, %BF and %TF thresholds for increased prevalence of MS. Logistic regression models were used to examine the individual and joint association of BMI, %BF, and %TF with the risk of MS. When examined individually, an increased risk of MS was noted at BMI >= 24 kg/m[sup 2]; %BF>=32; and %TF>=53, respectively. Prevalence of MS was low (ranging from 0% to 2.2%) for individuals with a BMI<24 kg/m[sup 2], and increased to 7.1% with a BMI >= 24 kg/m[sup 2] (24.0-24.9 kg/m[sup 2]). Similar patterns were observed for low vs. high %BF (<32 vs. >=32) and %TF (<53 vs. >=-53). When examined jointly, among women with BMI<24 and using women with a %BF<32 and %TF<53 as a reference, women with a %TF >=53 alone had a 4.6-fold higher risk of MS (%95 CI 1.8-12.0), women with a %BF >= 32 alone had a 3.8-fold higher risk of MS (95% CI 0.4-31.7); a similar pattern was observed among women with BMI>=24, and the highest risk was observed among women with %BF>=32 and %TF>=53 (OR=77.6, 95%CI 36.5-164.9). Our results suggest that in this Chinese population, a BMI >=24 cut-off was associated with markedly increased risk of MS and that independent of BMI, high %BF and high %TF each contributed to the increased risk of MS. [ABSTRACT FROM AUTHOR]