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In this study, the anti-penetration performance of polyurea/ASTM1405-steel composite plate subjected to high velocity projectile was analyzed. Two kinds of modified polyurea material (AMMT-053 and AMMT-055) were selected and a ballistic impact testing system including speed measuring target system and high-speed camera was designed. This experiment was conducted with a rifle and 5.8 mm projectile to explore the effects by the polyurea coating thickness, the polyurea coating position and the glass-fiber cloth on the anti-penetration performance of polyurea/ASTM1405-steel composite plate. The result showed that the effects of polyurea coating position were different between two types of polyurea, and that the effects of glass-fiber position were disparate between two types of polyurea as well. For AMMT-053 polyurea material, it was better to be on front face than on rear face; whereas for AMMT-055 polyurea, it was better to be on rear surface although the difference was very subtle. Additionally, formulas had been given to describe the relationship between the effectiveness of polyurea and the thickness of polyurea coating. In general, AMMT-055 had better anti-penetration performance than AMMT-053. Furthermore, five typical damage modes including self-healing, crack, local bulge, spallation and local fragmentation were defined and the failure mechanism was analyzed with the results of SHPB test. Additionally, the bonding strength played an important role in the anti-penetration performance of polyurea/steel composite plate.

The ongoing surge in demand for high-performance wearable sensors for precisely monitoring vital signs of the human body or the surrounding environment has inspired the relentless pursuit of biocompatible and biodegradable advanced materials. Cellulose, as a class of well-known natural biopolymer on the Earth, presents distinctive integrated merits of good biocompatibility and biodegradability, easy processability into diverse material formats, and sustainable production on a large scale, as well as intrinsic shape anisotropy, surface charge/chemistry, and superior physical and mechanical properties. Such unique advantages have driven constant innovations in wearable and smart cellulose-containing sensors in the past few years. With the rapid development of fabrication techniques in material processing and progress in research, cellulose has been engineered into multidimensional architectures including 1D (nanofibers, fibers, and yarns), 2D (paper, films, and fabrics), and 3D (hydrogels, aerogels, foams, and sponges), which are further transformed into electrically conductive carbonaceous materials with tailorable structures and properties. Cellulose-derived materials have been developed as flexible biosupports or biosubstrates, sensing layers, electrodes and active components for wearable sensors by virtue of their favorable and unique material merits. In this review, the recent advances in the development of multidimensional and multifunctional cellulose-derived materials are discussed for wearable sensors toward healthcare and environment monitoring. First of all, the unique hierarchical and chemical structures and properties of cellulose are briefly introduced. Then, we summarize the fabrication strategies for processing cellulose into materials with multidimensional architectures. Additionally, the design and functionality of flexible wearable sensors developed with multidimensional cellulose-derived materials as biosubstrates, electrodes, active layers, and sensing components are presented in detail. In particular, cellulose-based advanced materials for self-powered sensors are also highlighted. Finally, some prospects on the future challenges in this emerging research field of designing cellulose-derived materials for wearable sensors are illustrated. This review may provide insightful inspiration for the design and utilization of cellulosic composites in flexible electronic devices with high-performance.

The application of conductive hydrogels in intelligent biomimetic electronics is a hot topic in recent years, but it is still a great challenge to develop the conductive hydrogels through a rapid fabrication process at ambient temperature. In this work, a versatile poly(acrylamide) @cellulose nanocrystal/tannic acid-silver nanocomposite (NC) hydrogel integrated with excellent stretchability, repeatable self-adhesion, high strain sensitivity, and antibacterial property, was synthesized via radical polymerization within 30 s at ambient temperature. Notably, this rapid polymerization was realized through a tannic acid-silver (TA-Ag) mediated dynamic catalysis system that was capable of activating ammonium persulfate and then initiated the free-radical polymerization of the acrylamide monomer. Benefiting from the incorporation of TA-Ag metal ion nanocomplexes and cellulose nanocrystals, which acted as dynamic connecting bridges by hydrogen bonds to efficiently dissipate energy, the obtained NC hydrogels exhibited prominent tensile strain (up to 4000%), flexibility, self-recovery, and antifatigue properties. In addition, the hydrogels showed repeatable adhesiveness to different substrates (e.g., glass, wood, bone, metal, and skin) and significant antibacterial properties, which were merits for the hydrogels to be assembled into a flexible epidermal sensor for long-term human-machine interfacial contact without concerns about the use of external adhesive tapes and bacterial breeding. Moreover, the remarkable conductivity (σ ∼ 5.6 ms cm-1) and strain sensitivity (gauge factor = 1.02) allowed the flexible epidermal sensors to monitor various human motions in real time, including huge movement of deformations (e.g., wrist, elbow, neck, shoulder) and subtle motions. It is envisioned that this work would provide a promising strategy for the rapid preparation of conductive hydrogels in the application of flexible electronic skin, biomedical devices, and soft robotics.

Most ferroelectric crystals have their own set of unique characteristics, and ammonium sulfate (NH4)2SO4 is no exception. We report on two previously unidentified features in ammonium sulfate: (1) ...

Deregulated glucose and lipid metabolism are the primary underlying manifestations associated with diabetes mellitus (DM) and non-alcoholic fatty liver disease (NAFLD). This study aims to investigate the role of Gm10804, a novel long non-coding RNA (lncRNA), in regulating hepatic glucose and lipid metabolism in DM complicated with NAFLD (DM-NAFLD). Mouse primary hepatocytes exposed to high glucose (HG) were used as a cell model. A mouse DM-NAFLD model was established by high-energy feeding combined with intraperitoneal injection of streptozotocin. The results showed that Gm10804 expression was upregulated in HG-treated hepatocytes and livers from DM-NAFLD mice. Results in hepatocytes in vitro demonstrated that Gm10804 overexpression aggravated, whereas Gm10804 silencing abrogated HG-induced increase in intracellular triglyceride (TG) content, lipid accumulation and expression of hepatic lipogenic proteins (sterol regulatory element-binding proteins 1-c [SREBP-1c] and fatty acid synthase [FAS]) and enzymes for gluconeogenesis (phosphoenolpyruvate carboxykinase [PEPCK] and glucose-6-phosphatase [G6Pase]). Further in vivo assays showed that lentivirus-mediated hepatic knockdown of Gm10804 alleviated hepatic steatosis and lipid accumulation, and decreased expression of hepatic PEPCK, G6Pase, SREBP-1c and FAS in DM-NAFLD mice. In summary, Gm10804 knockdown attenuates hepatic lipid accumulation by ameliorating disorders of hepatic glucose and lipid metabolism in DM-NAFLD. SIGNIFICANCE OF THE STUDY: We first discovered that Gm10804 knockdown attenuated hepatic lipid accumulation by ameliorating disorders of hepatic glucose and lipid metabolism in DM-NAFLD. These results help to understand the pathogenesis and development of DM-NAFLD and provide some clues for further understanding the regulation of lncRNAs in glucose and lipid metabolism.

In this work, three benzodithiophene-benzotriazole alternated wide band gap copolymers attaching symmetric or asymmetric conjugated side chains, namely, PDBTFBTA-2T, PBDTFTBA-TSi, and PBDTFBTA-2Si, were developed for efficient nonfullerene polymer solar cells. The symmetry effect of the side chains was investigated in detail on the overall properties of these donor polymers. The results demonstrated that the introduced siloxane functional groups showed less effect on the absorption and frontier orbital levels of the prepared polymers but had a significant effect on the miscibility between these polymer donors and the nonfullerene acceptor. When increasing the content of siloxane functional groups, the miscibility of the polymer donors and Y6 would be improved, leading to the decreased domain size and more mixed domains. Interestingly, the active blend based on PBDTFTBA-TSi with asymmetric side chains exhibited more balanced miscibility, carrier mobility, and phase separation, benefiting exciton diffusion and dissociation. Therefore, a champion power conversion efficiency (PCE) of 14.18% was achieved finally in PBDTFTBA-TSi devices, which was 20.6 and 19.0% higher than the symmetric counterparts of PBTFBTA-2T devices (PCE = 11.76%) and PBDTFBTA-2Si devices (PCE = 11.92%), respectively. This work highlights that the asymmetric side-chain engineering based on siloxane functional groups is a promising design strategy for high-performance polymer donor semiconductors.

Ethanol is the most extensively used oxygenate for spark ignition (SI) engines. In comparison with ethanol, n-butanol exhibits a number of desirable properties for use in SI engines, which has proved to be a very promising oxygenated alternative fuel in recent years. However, the dehydration and recovery of bio-n-butanol consume extra money and energy in the acetone-n-butanol-ethanol (ABE) fermentation process. Hence, we focus on the research of ABE as a potential oxygenated alternative fuel in SI engines. The combustion, performance, and emission characteristics of B30, E30, ABE30 (i.e., 30 vol.% n-butanol, ethanol, and ABE blended with 70 vol.% gasoline), and G100 (pure gasoline) were compared in this study. The comparison results between B30, E30, and ABE30 at stoichiometric conditions show that ABE30 presents retarded combustion phasing, higher brake thermal efficiency, lower CO emissions, higher UHC emissions, and similar NOx emissions. In comparison with G100 under various engine loads and equivalence ratios, for the most part, ABE30 exhibits 1.4% higher brake thermal efficiency, 14% lower carbon monoxide, 9.7% lower unburned hydrocarbons, and 23.4% lower nitrogen oxides. It is indicated that ABE could be served as the oxygenate in spark ignition engine due to its capability to improve energy efficiency and reduce pollutant emissions.

Finding effective molecular design strategies to enable efficient charge generation and small energy loss is among the long-standing challenges in developing high performance non-fullerene organic solar cells (OSCs). Recently, we reported Y-series non-fullerene acceptors with an electron-deficient-core-based fused structure (typically Y6), opening a new door to achieve high external quantum efficiency (∼80%) while maintaining low energy loss (∼0.57 eV). On this basis, further reducing the energy losses and ultimately improving the performance of OSCs has become a research hotspot. In this paper, we design and synthesize a new member of the Y-series acceptor family, Y18, which adopts a fused benzotriazole segment with unique luminescence properties as its electron-deficient core. Compared to Y6, the benzotriazole-based acceptor Y18 exhibits extended optical absorption and higher voltage. Consequently, the device delivers a promising power conversion efficiency of 16.52% with a very low energy loss of 0.53 eV. Further device optimization by exploiting a ternary blend strategy allowed us to achieve a high efficiency of 17.11% (certified as 16.76% by NREL). Y18 may become one of the most important candidate materials for its broader absorption spectra and higher voltage of Y18 (compared to Y6) in the OSCs field.

Low cost photovoltaic materials and green solvent processing are important issues for commercial application of organic solar cells (OSCs). Here, we fabricated high-performance OSCs based on the low-cost conjugated polymer PTQ10 as a donor and the small molecule n-type organic semiconductor HO-IDIC-2F as an acceptor, using non-halogen tetrahydrofuran (THF) as the processing solvent. The power conversion efficiency (PCE) of the as-cast OSCs reached 12.20%, which is comparable with the ones processed with chloroform (CF) (12.43%). Thermal stability of the active layer was also studied by thermal treatment at 100 °C for 8 hours. As a result, the active layer morphology remained unchanged and the PCE of the devices still reached 12.13%, indicating a good thermal-stability of the PTQ10:HO-IDIC-2F blend film. As is commonly known, for OSCs fabricated on larger scales, the layer-by-layer (LL) method generally provides more advantages than the traditional D–A blend solution-processing method. Therefore, to test the compatibility of the THF solvent in the LL method, we fabricated blade-coated LL devices with THF as a single type of solvent for both the donor and acceptor, and the PCE could reach up to 11.85%. The surprisingly high performance of the blade-coated OSC based on the green solvent indicates that PTQ10 is a promising donor to be processed in green solvent for LL technology in the future.

Four new metal–organic frameworks, {[Zn(L)(dcdps)]}n (1), {Zn(L)(bdc)}n (2), {[Cd(L)(oba)]·0.5DMF}n (3), and {[Cd(L)(bdc)·2H2O]·2DMF}n (4) [L = 4,4′-(2,5-bis(methylthio)-1,4-phenylene)dipyridine; H...

Perfluorooctanoic acid (PFOA) and arsenic are ubiquitous environmental contaminants and could co-exist in soil. However, data on their possible combined toxic effects on terrestrial organisms are still lacking. In this study, we exposed earthworm Eisenia fetida to artificial soil spiked with different sub-lethal levels of PFOA, arsenite (As(III)) or their mixture for 28 days. The bioaccumulation and multi-biomarker responses in the earthworms were measured. Results showed that the co-existence of PFOA and As(III) in soil enhanced the bioaccumulation of arsenic while reduced the bioaccumulation of PFOA. Most selected biomarkers exhibited significant responses at higher exposure levels and indicated oxidative damages. Biomarker Response Index (BRI) was used to integrate the multi-biomarker responses and the results showed significant dose-effect relationships between biological health status and exposure levels. Moreover, variation analysis of multi-biomarkers and BRI proved that As(III) exhibited more toxicity than PFOA to the earthworms. Based on BRI results, Effect Addition Index (EAI) was calculated to evaluate the joint effects of the two toxicants. According to EAI, the joint toxicity of PFOA and As(III) was related to exposure concentration, changing from synergism to slight antagonism with the increase of exposure level. These results provide valuable toxicological information for the risk assessment of co-exposure to PFOA and arsenic in the soil environment. Moreover, this study proved that BRI is an effective tool to integrate multi-biomarker responses, and its combination with EAI provides a useful combined approach to evaluate the joint effects of mixed contamination systems.

Polymer solar cells (PSCs) have achieved great progress recently, benefiting from the rapid development of narrow bandgap small molecule acceptors and wide bandgap conjugated polymer donors. Among the polymer donors, the D-A copolymers with quinoxaline (Qx) as A-unit have received increasing attention since the report of the low-cost and high-performance D-A copolymer donor based on thiophene D-unit and difluoro-quinoxalline A-unit in 2018. In addition, the weak electron-deficient characteristic and the multiple substitution positions of the Qx unit make it an ideal A-unit in constructing the wide bandgap polymer donors with different functional substitutions. In this review article, recent developments of the Qx-based D-A copolymer donors, including synthetic method of the Qx unit, backbone modulation, side chain optimization, and functional substitution of the Qx-based D-A copolymers, are summarized and discussed. Furthermore, the application of the Qx-based D-A copolymers as hole transport material in perovskite solar cells (pero-SCs) is also introduced. The focus mainly on the molecular design strategies and structure-properties relationship of the Qx-based D-A copolymers, aiming to provide a guideline for developing high-performance Qx-based D-A copolymers for the applications as donor in PSCs and as hole transport material in pero-SCs.

Optimization of morphology and precise control of miscibility between donors and acceptors play an important role in improving the power conversion efficiencies (PCEs) of all-small-molecule organic solar cells (SM-OSCs). Besides device optimization, methods such as additives and thermal annealing are applied for finely tuning bulk-heterojunction morphology; strategies of molecular design are also the key to achieve efficient phase separation. Here, a series of A-D-A-type small-molecule donors (SM4, SM8, and SM12) based on benzodithiophene units were synthesized with different lengths of alkylthio side chains to regulate crystallinity, and their miscibility with the acceptor (BO-4Cl) was investigated. Consequently, SM4 with a short alkylthio substituent had a high crystallization propensity, leading to the oversized molecular domains and the poor morphology of the active layer. Meanwhile, SM12 with a longer alkylthio substituent showed weak crystallinity, causing a relatively looser π-π stacking and thus adversely affecting charge-carrier transport. The SM-OSC based on the small-molecule donor SM8 with a mid-length alkylthio substituent achieved a better PCE over 13%, which was attributed to a more harmonious blend miscibility without sacrificing carrier-charge transport. Eventually, the modulation of phase separation and miscibility via controlling the lateral side chains has proven its potential in optimizing the blend morphology to aid the development of highly efficient SM-OSCs.

Different types of magnetism arise mainly from how electrons move and interact with each other. In this work, we show how protons (H+) also exhibit magnetic behavior. We measured the magnetic susce...

In this work, the composite hydrogel toughening behaviors as manifested by strain rate-dependent viscoelastic properties and enhanced fracture mechanics, that is, suppressed catastrophic crack propagation with increased resistance, are systematically examined by using cellulose nanofibrils (CNFs) as fillers in the polyacrylamide (PAAm) matrix. The uniaxial deformation tests show that the tearing energy increases with crack velocity and becomes dominated by the viscoelastic energy dissipation in front of the crack tip. The creep dynamics of the composite hydrogels under a constant stress is examined, and the results indicate that the incorporation of the CNF pronouncedly suppresses the creep deformation. In addition, the microdeformation and failure mechanisms are analyzed through the observation of morphology of arrested crack tips and the damage zone by transmission electron microscopy and scanning electron microscopy. By aligning the CNF along the crack direction, it is possible to focus on the study of interfacial slip mechanics and identify the role of interfacial slip during the energy dissipation process. The results indicate that the CNFs are largely orientated parallel to the loading direction to maximize the energy dissipation, where the initiation of crack propagation is the primary fracture mechanism in composite hydrogels. The coarse feature on the composite fracture surface implies that the CNF initiates deflection of crack propagation fronts and thus increases the strain energy for continuation of the fracture. It is envisioned that with the incorporation of interdisciplinary strategies, one can rationally combine multiple approaches toward the creation of nanocomposite hydrogels with enhanced mechanical properties.

Bifunctional Na(Y0.8-xDyxYb0.18Er0.02)F4(x = 0,5%, 10%, 15%, 20%, 25%, 30%) nanoparticles (NPs) are synthesized by the solvothermal method. Green and red upconversion emissions and the paramagnetic property simultaneously highly depend on Dy3+ content in Na(Y0.8-xDyxYb0.18Er0.02)F4 (x = 0, 5%, 10%, 15%, 20%, 25%, 30%). The tuning of upconversion emission intensity is resulted from the competition of the resonance energy transfer between Dy3+ and Er3+, transition possibility of Yb3+→ Er3+, and concentration quenching, which is depended on the doping level of Dy3+. It is found that the magnetization of Na(Y0.8-xDyxYb0.18Er0.02)F4 NPs nonmonotonously depends on the concentration of Dy3+ ions, which indicates that there may be the occurrence of the magnetic coupling of Dy3+ ions and antiferromagnetic coupling of Dy3+, Y3+, Yb3+, and Er3+ ions. The optimal content of Dy3+ ions for simultaneous control of photoluminescence emission and paramagnetic properties is 15%. These conclusions are important for tuning optical properties and magnetization in bifunctional NPs simultaneously.

Al doped zinc magnesium oxide (Zn1-xMgxO:Al) thin films with tunable optical bandgap (3.48 eV–3.66 eV) and resistivity level of 10−3 Ω·cm were prepared by sol-gel process. The effect of the Mg incorporation on the structural, electrical and optical properties was studied by analyzing the results of X-ray diffraction diffractograms, transmittance spectra, Hall measurement and X-ray photoelectron spectroscopy. Mg incorporation influences the crystal structure through reducing the c-axis lattice constant. Blueshift of absorption edge with Mg incorporation manifests the bandgap widening effect. Mg incorporation also increases the film resistivity through decreasing Hall mobility and carrier concentration. Employed as the front electrode, these Zn1-xMgxO:Al thin films improved the blue response of hydrogenated amorphous silicon solar cells through reducing the optical loss in ZnO:Al. Zn1-xMgxO:Al with x ≤ 0.13 enables an open-circuit voltage (Voc) of about 0.9 V and a fill factor (FF) of about 0.7. The Zn0.87Mg0.13O:Al empowers a gain of about 9% in short-circuit current density relative to ZnO:Al via the bandgap widening and the improved refractive-index-matching, while the Zn0.80Mg0.20O:Al deteriorates Voc and FF through increasing the downward band bending at the Zn1-xMgxO:Al/p-a-SiC:H interface. This work paves the way for applying the sol-gel derived Zn1-xMgxO:Al thin films to optoelectronic devices such as ultraviolet light detector, ultraviolet light emitting diodes and solar cells.

Uniform urchin-like polyaniline/magnetic carbon sphere (PANI/p-C/NiFe2O4) hybrid with superior electromagnetic wave absorption properties was successfully fabricated, and its morphologies and structures were investigated via SEM, XPS, XRD and FT-IR. Due to the fairly good matching of dielectric loss and magnetic loss, the PANI/p-C/NiFe2O4 hybrid sample with thickness of 2.5 mm showed a minimum reflection loss value up to −37 dB in the frequency range of 2–18 GHz, the effective absorption band width of 3.9 GHz, and the excellent electromagnetic wave absorption property both in absorption efficiency and effective absorption band.

Although self-healing gels with structural resemblance to biological tissues attract great attention in biomedical fields, it remains a dilemma for combination between fast self-healing properties and high mechanical toughness. On the basis of the design of dynamic reversible cross-links, we incorporate rigid tannic acid-coated cellulose nanocrystal (TA@CNC) motifs into the poly(vinyl alcohol) (PVA)-borax dynamic networks for the fabrication of a high toughness and rapidly self-healing nanocomposite (NC) hydrogel, together with dynamically adhesive and strain-stiffening properties that are particularly indispensable for practical applications in soft tissue substitutes. The results demonstrate that the obtained NC gels present a highly interconnected network, where flexible PVA chains wrap onto the rigid TA@CNC motifs and form the dynamic TA@CNC-PVA clusters associated by hydrogen bonds, affording the critical mechanical toughness. The synergetic interactions between borate-diol bonds and hydrogen bonds impart a typical self-healing behavior into the NC gels, allowing the dynamic cross-linked networks to undergo fast rearrangement in the time scale of seconds. Moreover, the obtained NC hydrogels not only mimic the main feature of biological tissues with the unique strain-stiffening behavior but also display unique dynamic adhesiveness to nonporous and porous substrates. It is expected that this versatile approach opens up a new prospect for the rational design of multifunctional cellulosic hydrogels with remarkable performance to expand their applications.

An efficient copper(I)-catalyzed enyne oxidation/cyclopropanation for the modular synthesis of cyclopropane derivatives is described, which represents the first non-noble metal-catalyzed enynes oxidation/cyclopropanation by the in situ generated α-oxo copper carbenes. This protocol allows the assembly of valuable cyclopropane-γ-lactams in generally good to excellent yields with excellent diastereoselectivity. More significantly, the enantioselective version of enyne oxidation/cyclopropanation has been disclosed with chiral copper catalysts.

Houttuyniae Herba (HH) refers to the dried aerial part of Houttuynia cordata Thunb. (DHC) or the fresh whole grass of Houttuynia cordata Thunb. (FHC), where DHC are harvested in summer and FHC around the year. However, harvest seasons and processing methods (i.e., medicinal parts and drying process) might affect the quality of HH. To compare the essential oils (EOs) of DHC and FHC and their two harvest seasons, GC-MS analysis combined with chemometric analysis was applied. The results showed that the oil yield of FHC (0.076 ± 0.030%) was higher than that of DHC (0.038 ± 0.029%), and oil yield was higher in summer than in autumn (0.044 ± 0.029% for DHC1, 0.036 ± 0.028% for DHC2, 0.084 ± 0.026% for FHC1, and 0.067 ± 0.033% for FHC2, respectively). Moreover, hierarchical cluster analysis (HCA) and principal component analysis (PCA) successfully distinguished the chemical constituents of DHC and FHC oils. Additionally, according to orthogonal partial least squares discriminant analysis (OPLS-DA), eleven components were selected as chemical markers for discriminating DHC and FHC, and two and four chemical markers for discriminating two harvest seasons of DHC and FHC, respectively. Among these markers, the average contents of α-pinene, limonene, β-phellandrene, α-terpineol, 4-tridecanone, and ethyl decanoate were higher in FHC oils. In contrast, the average contents of nonanal, 1-nonanol, β-cyclocitral, n-hexadecanoic acid, and octadecanol were higher in DHC oils. Additionally, the contents of 4-tridecanone and ethyl decanoate were both higher in DHC1 oils than in DHC2 oils. Moreover, the contents of β-myrcene and β-phellandrene were higher in FHC1 oils, while the contents of 2,6-octadien-1-ol, 3,7-dimethyl-, acetate, and (z)-phytol were higher in FHC2 oils. For these reasons, this study provides a scientific basis for quality control and clinical medication.

Flexible electronics have been extensively explored for health monitoring, artificial intelligence, and soft robotics. However, it remains challenging to simultaneously achieve temperature and strain monitoring over a wide perception range that are highly analogous to natural human skin. Herein, an intelligent thermosensation zwitterionic hydrogel with superior low-temperature tolerance and conformal adhesion was successfully prepared for strain-temperature dual-modal sensors, based on the temperature-dependent self-association interactions of sulfobetaine methacrylate (SBMA) polymer chains and the incorporation of thermosensitive TEMPO-oxidized cellulose/polyaniline nanofibers (CPA NFs) in glycerol-water binary solvent system. Significantly, the TEMPO-oxidized cellulose acting as the reinforced skeleton guided the in-situ polymerization of polyaniline, while the tunneling current activated by thermal vibration of CPA NFs and the charge transfer caused by the spatial position adjustment collectively contributed to the superimposed signal recognition ability. By leveraging the glycerol molecules to inhibit the ice crystal growth without the compromise of flexibility (1095 %), strain sensitivity (GF = 1.25), and thermal responsiveness (TCR = 2.01% °C-1), the accurate determination paradigm for dual-modal strain and temperature sensor over a wide temperature range (-40-80 °C) was subtly achieved. Additionally, we corroborated that the conformal adhesion between zwitterionic active sites (e.g. –N+(CH3)3 or -SO3-) and dynamic interfaces was critical for minimizing interface slippage and delamination, as well as maintaining real-time electrical signal stability. The assembled zwitterionic epidermis sensor array that conformally adhered to fingers could realize the subtle signal identification and localized temperature detection, which presented promising prospects for designing the multi-modal skin-like responsiveness electronic skins that suitable for harsh temperature conditions.

Achieving efficient charge transfer at small frontier molecular orbital offsets between donor and acceptor is crucial for high performance polymer solar cells (PSCs). Here we synthesize a new wide band gap polymer donor, PTQ11, and a new low band gap acceptor, TPT10, and report a high power conversion efficiency (PCE) PSC (PCE = 16.32%) based on PTQ11-TPT10 with zero HOMO (the highest occupied molecular orbital) offset (ΔEHOMO(D-A)). TPT10 is a derivative of Y6 with monobromine instead of bifluorine substitution, and possesses upshifted lowest unoccupied molecular orbital energy level (ELUMO) of -3.99 eV and EHOMO of -5.52 eV than Y6. PTQ11 is a derivative of low cost polymer donor PTQ10 with methyl substituent on its quinoxaline unit and shows upshifted EHOMO of -5.52 eV, stronger molecular crystallization, and better hole transport capability in comparison with PTQ10. The PSC based on PTQ11-TPT10 shows highly efficient exciton dissociation and hole transfer, so that it demonstrates a high PCE of 16.32% with a higher Voc of 0.88 V, a large Jsc of 24.79 mA cm-2, and a high FF of 74.8%, despite the zero ΔEHOMO(D-A) value between donor PTQ11 and acceptor TPT10. The PCE of 16.32% is one of the highest efficiencies in the PSCs. The results prove the feasibility of efficient hole transfer and high efficiency for the PSCs with zero ΔEHOMO(D-A), which is highly valuable for understanding the charge transfer process and achieving high PCE of PSCs.

Epidermal flexible devices can continuously and real-time record the electrical potential changes from human skin, which is essential for chronic disease diagnosis and smart health monitoring. However, it remains challenging to fabricate high-performance epidermal dry electrodes with excellent self-adhesive while maintaining excellent biodegradability as well as high mechanical performance and low contact impedance. Herein, we fabricate an epidermal dry electrode with high mechanical performance, low contact impedance and excellent self-adhesive by coating polypyrrole (Ppy) conductive layer and calcium (Ca)-modified SF adhesive layer on acid-modified silk (AM-SF)/cellulose nanocrystals (CNC) films. The AM-SF could effectively promote the absorption and intercalation of Ppy into the SF network, endowing the tight integration between the Ppy conductive layer and the AM-SF/CNC films and improving the conductivity of Ppy@AM-SF/CNC films. On the other side, the Ca ions in the Ca-modified SF adhesive layer capture water molecules from the atmosphere and result in a much higher flowability to allow conformal contact between Ca-modified SF and the human skin, leading to significantly low skin-electrode impedance. As a proof-of-concept, the Ppy@AM-SF/CNC electrodes are employed for both electrocardiography (ECG) and electromyography (EMG) recording. Interestingly, this electrode allows detaching from the skin by simple water rinsing to reduce skin-damage for people. Moreover, the Ppy@AM-SF/CNC electrodes possess excellent enzymatic degradability without leaving hazardous substances. This work offers a unique prospective for developing next-generation wearable healthcare devices in the era of personalized healthcare.

Background Sepsis is one of the common death factors in intensive care unit, which refers to the systemic inflammatory response syndrome caused by infection. It has many complications such as acute renal injury, shock, multiple organ dysfunction, and failure. The mortality of acute renal injury is the highest among the complications, which is a serious threat to the safety of patients and affects the quality of life. This study aimed to observe the changes in autophagy-related protein expressions in patients with acute kidney injury (AKI) after continuous renal replacement therapy (CRRT) and their impacts on prognosis. Methods 207 AKI patients visiting the Emergency Department of The First People’s Hospital of Xuzhou from January 2014 to February 2018 were recruited and treated with CRRT. Quantitative reverse transcription polymerase chain reaction (qRT-PCR) was applied to detect the expression of autophagy-related genes, including light chain 3 type II (LC3-II), autophagy-related 5 (Atg-5) and Beclin-1, in the monocytes of the patient’s peripheral blood before and after treatment. The levels of inflammatory mediators interleukin (IL)-1β and IL-6 were determined via enzyme-linked immunosorbent assay before and after treatment. The patient’s serum creatinine (Scr) level before and after treatment was measured using a full-automatic biochemistry analyser. Moreover, the treatment effect was graded after CRRT, and the relationship between the prognosis of patients and the autophagy-related proteins was observed. Results The Scr levels in the patients were significantly decreased after treatment with CRRT. Before treatment, the IL-1β and IL-6 blood levels were high in the patients, while the amounts were significantly reduced after CRTT. The expressions of LC3-II, Atg-5 and Beclin-1 in the monocytes of patients after treatment were significantly decreased compared with those before treatment. Compared with those in survived patients, the expression of autophagy-related proteins was significantly elevated in in patients died after one to three weeks after the treatment. IL-1β, IL-6, LC3-II and Beclin-1, but not Atg-5 values were significantly correlated with Scr. Conclusion The expression of LC3-II, Atg-5 and Beclin-1 in the monocytes of patients may change prominently after treatment with CRRT, so they are expected to be regarded as new prognostic indicators for AKI patients.

Summary In contrast to conventional colloidal quantum dots (CQDs), management of insulating ligands on perovskite CQDs is challenging because their ionic bonds are highly vulnerable to polar solvents. Consequently, there have been only a few examples of perovskite CQD solar cells incorporating relatively robust inorganic perovskite of which optoelectronic properties are not ideal for photovoltaic devices. Here, we report efficient and stable CQD solar cells based on formamidinium lead triiodide (FAPbI3) CQDs realized by rational surface regulation. Tailoring polarity of antisolvents for the post-synthetic process enabled effective removal of the insulating ligands on FAPbI3 CQDs while preserving perovskite cores. Owing to the enhanced inter-dot electrical coupling, a power-conversion efficiency of 8.38% was demonstrated. Furthermore, the FAPbI3 CQDs-based devices showed superior stability over those of bulk FAPbI3 devices. Thermodynamic and crystallographic analyses revealed that enhanced contribution of the surface energy and lattice contraction contribute to their superior stability.

It is very important to fine-tune the nanoscale morphology of donor:acceptor blend active layers for improving the photovoltaic performance of all-small-molecule organic solar cells (SM-OSCs). In this work, two new small molecule donor materials are synthesized with different substituents on their thiophene conjugated side chains, including SM1-S with alkylthio and SM1-F with fluorine and alkyl substituents, and the previously reported donor molecule SM1 with an alkyl substituent, for investigating the effect of different conjugated side chains on the molecular aggregation and the photophysical, and photovoltaic properties of the donor molecules. As a result, an SM1-F-based SM-OSC with Y6 as the acceptor, and with thermal annealing (TA) at 120 °C for 10 min, demonstrates the highest power conversion efficiency value of 14.07%, which is one of the best values for SM-OSCs reported so far. Besides, these results also reveal that different side chains of the small molecules can distinctly influence the crystallinity characteristics and aggregation features, and TA treatment can effectively fine-tune the phase separation to form suitable donor-acceptor interpenetrating networks, which is beneficial for exciton dissociation and charge transportation, leading to highly efficient photovoltaic performance.

Fluorene is a priority pollutant in water listed by U.S. Environmental Protection Agency. A fluorescent probe using Eu(III)-marked polystyrene nanoparticles (EuNPs) labelled with a monoclonal antibody (MAb) was synthesized and an immunochromatographic assay (ICA) based on the probe (EuNPs-MAb) was developed for rapid and sensitive detection of fluorene in water samples. The concentration of fluorene was inversely proportional to fluorescence intensity values of T-line in the range 0.98–62.50 ng/mL. The limit of detection (LOD) for quantitative detection of fluorene was 0.09 ng/mL. Recoveries of fluorene in various water samples ranged from 81.50% to 103.00% and coefficients of variation (CVs) were below 13%, which were in a good agreement with those of traditional ELISA (R2 = 0.99). The assay can be performed within 30 min. The integrated ICA strip gave higher sensitivity and reliable reproducibility. It could be a potential method for rapid and sensitive detection of fluorene in water samples.

The remarkable progress in efforts to prepare conductive self-healing hydrogels mimicking human skin’s functions has been witnessed in recent years. However, it remains a great challenge to develop an integrated conductive gel combining excellent self-healing and mechanical properties, which is derived from their inherent compromise between the dynamic cross-links for healing and steady cross-links for mechanical strength. In this work, we design a tough, self-healing, and self-adhesive ionic gel by constructing synergistic multiple coordination bonds among tannic acid-coated cellulose nanocrystals (TA@CNCs), poly(acrylic acid) chains, and metal ions in a covalent polymer network. The incorporated TA@CNC acts as a dynamic connected bridge in the hierarchically porous network mediated by multiple coordination bonds, endowing the ionic gels the superior mechanical performance. Reversible nature of dynamic coordination interactions leads to excellent recovery property as well as reliable mechanical and elect...

The Sandaozhuang deposit (0.55 Mt WO3 at 0.112% and 0.75 Mt Mo at 0.109%), located in the southern margin of the North China Craton, is one of the largest W-Mo deposits in the world. This study carried out in-situ elemental analyses on skarn minerals, as well as elemental and Sr-Nd isotopic analyses on scheelites from the deposit, to constrain the metal source and fluid evolution of the deposit. Three generations of scheelite (Sch A to C) were identified based on petrographic observations, including prograde skarn and diopside-plagioclase hornfels-hosted Sch A, retrograde skarn-hosted Sch B, and quartz vein-hosted Sch C. Varieties of REE patterns in the scheelite are mainly controlled by different substitution mechanisms and crystallization of REE-enriched skarn minerals. The Mo contents decrease from early generation Sch A (1.57–24.45%) to Sch B (0.19–1.52%) and finally to Sch C (0.20–0.97%), and Eu anomalies of scheelite change from negative to positive and then back to negative values. The Sandaozhuang deposit is characterized by Mg-rich clinopyroxene (Di40-81Hd17-47), and grossularite–andradite (And22–89Gro6-77), similar to well-studied oxidized W skarn deposits worldwide, but the andradite contents of one garnet grain in the late prograde stage, decrease from the core (84.09%) to rim (75.12%). Composition changes of scheelite and garnet indicate that the ore-forming fluids changed from oxidized to reduced state in the skarn stage then to oxidized state in the quartz-sulfide stage, and the variations in redox state favoured the muti-stage Mo mineralization. The relatively uniform Y/Ho ratios of the Nannihu granite porphyry and scheelite imply that the ore-forming fluids are mainly derived from the porphyry. Scheelites from Sandaozhuang are characterized by low eNd(t) values (−14.7 to − 11.8), which are consistent with those for the Nannihu granite porphyry. Such a coincidence indicates that ore-forming fluids were mainly derived from the ore-hosting porphyry. However, the initial 87Sr/86Sr ratios of scheelites (0.7158–0.7295) are significantly higher than those of the Nannihu granite porphyry and other granites in the Luanchuan ore district (0.7047–0.7098), indicating that the Neoproterozoic Luanchuan Group with radiogenic Sr isotopic compositions contributed to tungsten mineralization, and the intense fluid-rock interaction between the ore-forming fluids derived from the granite porphyry and the Luanchuan Group country rocks may play an important role in tungsten mineralization.

In this work, we reported a facile reduction approach for fabrication of water-soluble and ultrabright Cu nanoclusters with core-shell structure. A certain amount of reducing agent as NaBH4 was introduced into the polyethyleneimine-stablized Cu nanoclusters (CuNCs@PEI) system, which exhibited 4-fold fluorescence enhancement along with a blue shift of the emission peak. The variations of morphology, valence states and functional groups demonstrated that a Cu shell was formed surround CuNCs (defined as CuNCs-Cu@PEI), attributable to metal complex (PEI-Cu+ and PEI-Cu2+) reduction. The effect of core-shell morphology on luminous and electron relaxation mechanism of CuNCs-Cu@PEI was investigated via temperature-dependent steady and time-resolved fluorescence measurements. The CuNCs-Cu@PEI with a high fluorescence quantum yields (QYs) of 22.59 % were able to homogeneously disperse in aqueous phase, indicating their potential applications in biological labeling, sensing and in vivo imaging. Finally, the CuNCs-Cu@PEI was employed as a fluorescence probe to determine 4-nitrophenol, of which the detection limit was much lower than initial CuNCs@PEI.

A C2v-symmetric core, dithienocyclopentaspiro[fluorene-9,9′-xanthene], was used as the central block for the first time to design and synthesize A-D-A type small molecule acceptors for nonfullerene polymer solar cells (PSCs), and two new small molecule acceptors of TSFX-2F and TSFX-4F were synthesized based on the C2v-symmetric core. The two TSFX-based acceptors show high thermal stability, strong absorption in the wavelength region of 550–750 nm and appropriate energy levels. The PSCs with the broad bandgap polymer J71 as donor and TSFX-2F as acceptor demonstrated power conversion efficiency (PCE) of 9.42% with open circuit voltage (Voc) of 0.89 V, short circuit current density (Jsc) of 15.27 mA cm−2 and fill factor (FF) of 69.30%, while the PSC based on J71:TSFX-4F shows a PCE of 8.47% with Voc of 0.83 V, Jsc of 15.48 mA cm−2 and FF of 66.16%. The higher Voc of the PSC based on J71: TSFX-2F is benefitted from the up-shifted LUMO energy level of the TSFX-2F acceptor, and its higher FF can be ascribed to the higher and more balanced hole and electron mobilities of the J71: TSFX-2F active layer. This work demonstrates that the new C2v-symmetric building block is a promising central D-unit for the design and synthesis of new structured norfullerene acceptors for high-performance PSCs.

Miscibility and morphology of the active layers have significant influence on the photovoltaic performance of polymer solar cells (PSCs). Chemical strategies, especially molecular structure design, have been proven to be crucial for polymer donor materials. In this work, two wide bandgap D-A copolymer donors composed of tripropylsilyl substituted bithienyl-benzodithiophene as donor (D) unit and dialkyl substituted bithiazole as acceptor (A) unit were designed and synthesized. By introducing thiophene π-bridges into the backbone, the miscibility and morphological properties of the materials are effectively tuned, leading to tremendous progress in power conversion efficiency from 0.95% to 10.73% with m-ITIC as the acceptor. The results demonstrate that manipulating molecular distortion can be an effective strategy to regulate molecular self-assembly behavior of the polymer donors and achieve excellent aggregation properties, blend miscibility, and photovoltaic performance of the PSCs.

A simple luminescence sensor, based on polyethyleneimine protected silver nanoclusters (AgNCs@PEI) is successfully fabricated via one-pot reduction method. The obtained AgNCs@PEI are characterized by high-resolution transmission electron microscopy (HR-TEM), Dynamic light scattering (DLS), transient and steady-state fluorescence, and UV–vis spectroscopy. The NCs show large Stocks-shift (∼ 130 nm), high tolerability to extreme pH and high ionic strengths, and excellent photo-stability under UV irradiation, laying the basement for the practical applications. In addition, the sensor is used to detect the Co 2 + basing on the luminescence quenching, which is interfered by pH conditions (from pH 4.0 to pH 7.4). As a luminescence probe for Co 2 + ions, the detection limit of AgNCs@PEI is as low as 0.25 nM, which is much lower than that of many other reports. Additionally, the AgNCs@PEI possess the advantages of good selectivity, fast response and abroad linear detection. A linear response range in 0.5 nM–50 μM is achieved for Co 2 + when using 20 μM AgNCs@PEI in BR buffer solution (neutral condition pH 7.4). Incubation time of AgNCs@PEI toward Co 2 + is only 2 min and it can distinguish Co 2 + from other 13 metal ions. Furthermore, the probe (AgNCs@PEI) is applied to sensing and imaging of HeLa cells, showing low cytotoxicity and good sensitivity.

The back contact adhesion is the important factor of the microstructural performance which can determine the optoelectronic properties of the kesterite-based solar cells. Here, we present a rational and effective strategy to significantly enhance the back contact adhesion of Cu 2 (Zn,Cd)Sn(S,Se) 4 (CZCTSSe) absorber layers by insetting the appropriate thickness carbon-doping CZCTS thin films. We chose the oleylamine as the carbon-doping reagent which can generate a small amount of carbon in the annealing process. The suitable thickness carbon-doping CZCTS films can significantly change the crystal growth mechanism of CZCTSSe absorber layers, and eliminate the holes in the back contact. The efficiency of CZCTSSe solar cells fabricated by insetting the appropriate thickness carbon-doping CZCTS films is above 7%, and shows the excellent repeatability and long-term air stability compared with the control devices.

A urethane methacrylate monomer, 2-[(butylcarbamoyl)oxy]ethyl methacrylate (BEM), methyl methacrylate (MMA), and butyl acrylate (BA) were used to prepare latexes. The effects of polymer process (batch versus semi-batch), polymer composition, and the locus (core-shell) of urethane functionality in the latex particles were studied. Urethane functional latexes were evaluated by FT-IR, solid state nuclear magnetic resonance (SS-NMR), dynamic light scattering (DLS), gas chromatography (GC), differential scanning calorimetry (DSC), tensile and dynamic mechanical thermal analysis (DMTA). A compositional drift was observed for the batch polymerization which resulted in early formed polymers rich in MMA and BEM. This accounted for the higher modulus and tensile strength in latexes derived from batch polymerization. Both homogeneous and core-shell structures were prepared. The tensile modulus, tensile strength and elongation-at-break were all dependent on BEM content.

The influence of butyl acrylate (BA) and methyl methacrylate (MMA) on hydroxyl functionalized latexes was investigated. The hydrophobicity of the monomer feed was varied via the BA/MMA ratio. In addition to monitoring the effect of hydrophobic monomer feed on secondary nucleation, the polymerization kinetics and final latex properties were also obtained for comparison. Five different BA to MMA molar ratios were combined with five 2-hydroxyethyl methacrylate (HEMA) concentrations (0, 10, 20, 30 and 40 mol% in monomer composition). All latexes were synthesized through seeded semibatch emulsion polymerization process. Particle size distributions and average particle sizes of the latexes were determined by dynamic light scattering (DLS) and qualitatively compared with transmission electron microscope (TEM) images. The BA to MMA ratio significantly influences the boundary HEMA concentration at which homogeneous secondary nucleation occurs. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017

Bio-butanol is typically produced by acetone-butanol-ethanol (ABE) fermentation, however, the recovery of bio-butanol from the ABE mixture involves high costs and energy consumption. Hence it is of interest to study the intermediate fermentation product, i.e. ABE, as a potentially alternative fuel. In this study, an experimental investigation of the performance, combustion and emission characteristics of a port fuel-injection SI engine fueled with ABE-gasoline blends was carried out. By testing different ABE-gasoline blends with varying ABE content (0 vol%, 10 vol%, 30 vol% and 60 vol% referred to as G100, ABE10, ABE30 and ABE60), ABE formulation (A:B:E of 1:8:1, 3:6:1 and 5:4:1 referred to as ABE(181), ABE(361) and ABE(541)), and water content (0.5 vol% and 1 vol% water referred to as W0.5 and W1), it was found that ABE(361)30 performed well in terms of engine performance and emissions, including brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), carbon monoxide (CO), unburned hydrocarbons (UHC) and nitrogen oxides (NO x ) emissions. Then, ABE(361)30 was compared with conventional fuels, including E30, B30 (30 vol% ethanol or butanol blended with gasoline) and pure gasoline (G100) under various equivalence ratios and engine loads. Overall, a higher BTE (0.2–1.4%) and lower CO (1.4–4.4%), UHC (0.3–9.9%) and NO x (4.2–14.6%) emissions were observed for ABE(361)30 compared to those of G100 in some cases. Therefore, ABE could be a good alternative fuel to gasoline due to the environmentally benign manufacturing process (from non-edible biomass feedstock and without a recovery process), and the potential to improve energy efficiency and reduce pollutant emissions.

A series of new urethane methacrylate (UMA) monomers were synthesized with the reaction of ethylene carbonate and aliphatic amines, followed by the reaction with methacrylic anhydride. The monomers were characterized by 1H, 13C nuclear magnetic resonance (NMR), mass (MS), and Fourier transform infrared (FTIR) spectroscopies. Urethane latexes were prepared by monomer-starved semibatch polymerization of the new urethane methacrylates with methyl methacrylate (MMA) and butyl acrylate (BA). A uniform morphology and a unimodal particle distribution were observed by a combination of dynamic light scattering (DLS), ultrasound acoustic attenuation spectroscopy (UAAS), and transmission electron microscopy (TEM). The thermal stability, minimum film formation temperature (MFFT) and thermo-mechanical properties of the urethane latexes were also studied. The inclusion of urethane monomers appeared to have lowered the MFFT via a water plasticization effect, while enhancing the Tg of the final film properties.

Curcumin, a polyphenol compound extracted from the roots of turmeric plants, possesses anti-depressant effect by regulating the levels of neuroendocrine immunological factors. The purpose of this study was to investigate the anti-depressant effect of curcumin through nasal delivery. The results of phase solubility, Fourier transform infrared spectra, Differential scanning calorimetry, X-ray powder diffractometry and 1H NMR spectra assays showed that curcumin/hydroxypropyl-β-cyclodextrin complex had been obtained. The viscosity of hydrogel increased rapidly at the temperature range of 29-30 °C through the test of rheological property of Guanidine-Chitosan thermo-sensitive hydrogel. And the hydrogel had good mucoadhesion properties. The cumulative release rate of curcumin was 55% in 10 hours in vitro drug release test. Curcumin-loaded (14.6, 29.2 or 58.4 μg/kg) thermo-sensitive hydrogel could reduce the immobility time of mice in force swimming test and tail suspension test, while could not increase the independent behavioral activity of mice. In addition, curcumin-loaded (14.6, 29.2 or 58.4 μg/kg) thermo-sensitive hydrogel could increase the concentration of Norepinephrine, Dopamine, 5-Hydroxytryptamine and their metabolites in hippocampus and striatum. In conclusion, thermo-sensitive hydrogel delivery system can be seen as a promising formulation of curcumin for the treatment of depression through nasal delivery.

BACKGROUND: Over 19.5 million people worldwide abuse natural opiates, such as opium-derived products common in Central Asia and Middle East, and many of them also smoke cigarettes. However, there is little information on human exposure to carcinogens and other toxicants related to opiate use, alone or in combination with tobacco use. METHODS: Based on self-reported information, we randomly selected four groups of participants of the Golestan Cohort Study in Northeast Iran: 60 never users of either opiates or tobacco, 35 exclusive current cigarette smokers, 30 exclusive current opiate users, and 30 current opiate users who also smoked cigarettes (dual users; 21 smoked opiates and 9 took them by mouth). We quantified urinary concentrations of 39 exposure biomarkers in four chemical classes: tobacco alkaloids, tobacco specific nitrosamines (TSNAs), polycyclic aromatic hydrocarbons (PAHs), and volatile organic compounds (VOCs). Total nicotine equivalent (TNE) was used as a measure of nicotine dose. We used Oaxaca-Blinder decomposition to parse out the share of the biomarker concentrations explained by opiate use and nicotine dose. RESULTS: Exclusive opiate users and exclusive cigarette smokers had substantially higher concentrations of PAH and VOC biomarkers than never users of either product, but dual users had the highest concentrations. Decomposition analysis showed that opiate use contributed a larger part of the PAH concentrations than nicotine dose, and the sum of 2- and 3-hydroxyphenanthrene (∑(2,3)-phe) resulted almost completely (92%) from opiate use. Concentrations of most VOC biomarkers were explained by both nicotine dose and opiate use, but nicotine dose contributed more. Two acrylamide metabolites (AAMA: 90%, GAMA: 91%), the 1,3-butadiene metabolite (DHBM: 73%), and the dimethylformamide metabolite (AMCA: 72%) were more strongly explained by opiate use. Acrylamide metabolites and ∑(2,3)-phe were significantly higher in opiate smokers than opiate eaters; other biomarkers did not vary by the route of opiate intake. CONCLUSION: Both opiate users and cigarette smokers are exposed to several toxicants and carcinogens. Most biomarkers in opiate users were independent of exposure route, but a few were higher among opiate smokers than eaters. As opiates are widely used worldwide, exposure to some of these toxicants, including PAHs and VOCs, may have substantial global public health impact.

As a promising functional material, hydrogels have attracted extensive attention, especially in flexible wearable sensor fields, but it remains a great challenge to facilely integrate excellent mechanical properties, self-adhesion, and strain sensitivity into a single hydrogel. In this work, we present high in strength, stretchable, conformable, and self-adhesive chitosan/poly(acrylic acid) double-network nanocomposite hydrogels for application in epidermal strain sensor via in situ polymerization of acrylic acid in chitosan acid aqueous solution with tannic acid-coated cellulose nanocrystal (TA@CNC) acting as nanofillers to reinforce tensile properties, followed by a soaking process in a saturated NaCl solution to cross-link chitosan chains. With addition of a small amount of TA@CNC, the double-network nanocomposite hydrogels became highly adhesive and mechanically compliant, which were critical factors for the development of conformable and resilient wearable epidermal sensors. The salt-soaking process was applied to cross-link chitosan chains by shielded electrostatic repulsions between positively charged amino groups, drastically enhancing the mechanical properties of the hydrogels. The obtained double-network nanocomposite hydrogels exhibited excellent tunable mechanical properties that could be conveniently tailored with fracture stress and fracture strain ranging from 0.39 to 1.2 MPa and 370 to 800%, respectively. Besides, the hydrogels could be tightly attached onto diverse substrates, including wood, glass, plastic, polytetrafluoroethylene, glass, metal, and skin, demonstrating high adhesion strength and compliant adhesion behavior. In addition, benefiting from the abundant free ions from strong electrolytes, the flexible hydrogel sensors demonstrated stable conductivity and strain sensitivity, which could monitor both large human motions and subtle motions. Furthermore, the antibacterial property originating from chitosan made the hydrogels suitable for wearable epidermal sensors. The facile soaking strategy proposed in this work would be promising in fabricating high-strength multifunctional conductive hydrogels used for wearable epidermal devices.

High-work function (WF) transparent conductive thin films improve the performance of solar cells and organic light-emitting diodes by facilitating interfacial charge carrier transport. Al-doped ZnO (AZO) becomes a very promising transparent conductive material because of nontoxicity, abundant material resources, and low cost. To increase the WF of AZO without enhancing the series resistance of the device, a high-WF and low-resistance surface modifier of polycrystalline zinc molybdenum oxide (ZMO) was developed by utilizing thermal evaporation of MoO3 on the surface of AZO and a subsequent two-step annealing treatment. The first step of air annealing causes the formation of monoclinic ZnMoO4 nanocrystals in the ZMO modifier. This improves the WF of AZO from 3.83 to 4.86 eV by increasing the group electronegativity and cation oxidation state. Furthermore, the second step of N2 annealing decreases the resistivity of the polycrystalline ZMO by increasing the donor states of oxygen vacancies. The surface modification effect is verified by applying the ZMO-modified AZO to the front electrode of hydrogenated amorphous silicon thin-film solar cells. The low-resistance polycrystalline ZMO modifier not only increases light harvesting in the solar cells by improving interfacial refractive index matching but also improves the open-circuit voltage by modifying the interfacial band alignment. In particular, the modifier increases the fill factor by ca. 13% by reducing the series resistance of the device. These enable a gain of ca. 23% in photoelectric conversion efficiency compared to the unmodified AZO. The results suggest the feasibility to tune the WF and conductivity of a material independently.

A method is described here to prepare water-dispersible nitrogen-functionalized silicon nanoparticles (N-SiNPs). It consists of two steps, viz. etching of the oxidized shell of SiNPs and nitrogen-passivation of the exposed silicon. The resulting N-SiNPs have an average diameter of 2.6±0.7 nm and show blue fluorescence (with excitation/emission peaks at 340/420 nm). The fluorescence quantum yield is 23% and the decay time is in the nanosecond regime. Compared to etching methods using a plasma or hydrofluoric acid, the process described here (etching and passivation) is mild, continuous, fast, and air-compatible. The N-SiNPs modified with chlorotetracycline are shown to be a viable fluorescent probe for creatinine. Fluorescence drops in the 0 to 20 μM creatinine concentration range, and the limit of detection is 0.14 μM.

Soil salinity reduces plant growth and is a major factor that causes decreased agricultural productivity worldwide. Seaweed polysaccharides promote crop growth and improve plant resistance to abiotic stress. In this study, polysaccharides from brown seaweed Lessonia nigrescens polysaccharides (LNP) were extracted and further separated and fractionated. Two acidic polysaccharides (LNP-1 and LNP-2) from crude LNP were obtained and characterized. The latter had a lower molecular weight (MW) (40.2 kDa) than the former (63.9 kDa), but had higher uronic acid and sulfate content. Crude LNP and LNP-2 were composed of mannose, glucuronic acid, fucose, and xylose, whereas LNP-1 has little mannose. Moreover, the effects of the three polysaccharides on plant salt tolerance were investigated. The results showed that crude LNP, LNP-1, and LNP-2 promoted the growth of plants, decreased membrane lipid peroxidation, increased the chlorophyll content, improved antioxidant activities, and coordinated the efflux and compartmentation of intracellular ion. All three polysaccharides could induce plant resistance to salt stress, but LNP-2 was more effective than the other two. The present study allowed to conclude that both MW and sulfate degree contribute to salt resistance capability of polysaccharides derived from L. nigrescens.

Side-chain engineering has been an effective strategy in tuning electronic energy levels, intermolecular interaction, and aggregation morphology of organic photovoltaic materials, which is very important for improving the power conversion efficiency (PCE) of organic solar cells (OSCs). In this work, two D-A copolymers, PBQ5 and PBQ6, are designed and synthesized based on bithienyl-benzodithiophene (BDTT) as the donor (D) unit, difluoroquinoxaline (DFQ) with different side chains as the acceptor (A) unit, and thiophene as the π-bridges. PBQ6 with two alkyl-substituted fluorothiophene side chains on the DFQ units possesses redshifted absorption, stronger intermolecular interaction, and higher hole mobility than PBQ5 with two alkyl side chains on the DFQ units. The blend film of the PBQ6 donor with the Y6 acceptor shows higher and balanced hole/electron mobilities, less charge carrier recombination, and more favorable aggregation morphology. Therefore, the OSC based on PBQ6:Y6 achieves a PCE as high as 17.62% with a high fill factor of 77.91%, which is significantly higher than the PCE (15.55%) of the PBQ5:Y6-based OSC. The PCE of 17.62% is by far one of the highest efficiencies for the binary OSCs with polymer donor and Y6 acceptor.

Evaluations of gross mineralization (MNorg) and nitrification (ONH4) can be used to evaluate the supply capacity of inorganic N, which is crucial in determining appropriate N fertilizer application. However, the relevant research for banana plantations to date is limited. In this study, natural forest and banana plantations with different cultivation ages (3, 7, 10, and 22 y) were chosen in a subtropical region, and the 15N dilution technique was used to determine the gross MNorg and ONH4 rates. The objective was to evaluate the effect of the conversion of natural forests to banana plantations on inorganic N supply capacity (MNorg + ONH4) and other relevant factors. Compared to other natural forests in tropical and subtropical regions reported on by previous studies, the natural forest in this study was characterized by a relatively low MNorg rate and a high ONH4 rate in the soil, resulting in the presence of inorganic N dominated by nitrate. Compared to the natural forest, 3 y banana cultivation increased the MNorg and ONH4 rates and inorganic N availability in the soil, but these rates were significantly reduced with prolonged banana cultivation. Furthermore, the mean residence times of ammonium and nitrate were shorter in the 3 y than in the 7, 10, and 22 y banana plantations, indicating a reduced turnover of ammonium and nitrate in soil subjected to long-term banana cultivation. In addition, the conversion of natural forest to banana plantation reduced the soil organic carbon (SOC), total N and calcium concentrations, as well as water holding capacity (WHC), cation exchangeable capacity (CEC), and pH, more obviously in soils subjected to long-term banana cultivation. The MNorg and ONH4 rates were significantly and positively related to the SOC and TN concentrations, as well as the WHC and CEC, suggesting that the decline in soil quality after long-term banana cultivation could significantly inhibit MNorg and ONH4 rates, thus reducing inorganic N supply and turnover. Increasing the amount of soil organic matter may be an effective measure for stimulating N cycling for long-term banana cultivation.