Efficient Template-Catalyzed In Situ Polymerization for Carbon Xerogels with Large Specific Surface Area and High Adsorption.

The limited specific surface area (SSA), long preparation period, and high cost are significant challenges for carbon xerogels (CXs). To overcome these limitations, we propose an approach to prepare tannin-resorcinol-formaldehyde-based CXs through template-catalyzed in situ polymerization. ZnCl2 acts as a catalyst and significantly accelerates the polymerization reaction through the coordination of Zn2+ to the carbonyl group in formaldehyde, while atmospheric drying instead of special drying and without solvent exchange reduces the preparation period to 24 h. In addition, ZnCl2 acts as an activator for the formation of many pores. Plant-derived tannins not only reduce the preparation cost but also regulate the pore structure. The resulted CXs with hierarchical porous structures show an optimal SSA of 1308 m2/g, high adsorption capabilities (for cationic, nitrosoaniline dyes, metal, and nonmetallic ions, especially for methylene blue with 454.93 mg/g), low shrinkage down to 10%, and reusability with 92.9% retention after 5 cycles. This work provides a promising and cost-effective method for the large-scale preparation of porous carbon materials with large SSA, offering potential applications in adsorption, energy storage, and catalysis.

Ordered mesoporous nanofibers mimicking vascular bundles for lithium metal batteries.

Hierarchical self-assembly with long-range order above centimeters widely exists in nature. Mimicking similar structures to promote reaction kinetics of electrochemical energy devices is of immense interest, yet remains challenging. Here, we report a bottom-up self-assembly approach to constructing ordered mesoporous nanofibers with a structure resembling vascular bundles via electrospinning. The synthesis involves self-assembling polystyrene (PS) homopolymer, amphiphilic diblock copolymer, and precursors into supramolecular micelles. Elongational dynamics of viscoelastic micelle solution together with fast solvent evaporation during electrospinning cause simultaneous close packing and uniaxial stretching of micelles, consequently producing polymer nanofibers consisting of oriented micelles. The method is versatile for the fabrication of large-scale ordered mesoporous nanofibers with adjustable pore diameter and various compositions such as carbon, SiO2, TiO2 and WO3. The aligned longitudinal mesopores connected side-by-side by tiny pores offer highly exposed active sites and expedite electron/ion transport. The assembled electrodes deliver outstanding performance for lithium metal batteries.

Immunological effect of Lactic acid bacteria adjuvant on in ovo injection of Newcastle disease vaccine.

In ovo immunization of chicken embryos with live vaccines is an effective strategy to protect chickens against various viral pathogens. The immunogenic efficacies of in ovo administration of lactic acid bacteria (LAB) in combination with live Newcastle disease (ND) vaccine were investigated in this study. Four hundred healthy 1-day-old fertilized specific pathogen-free (SPF) eggs of similar weights were randomly assigned to one of four treatments, with five replicates of each treatment and a total of 20 for each replicate. On day 18.5 of incubation, in ovo injections were given. The treatment groups are as follows: (I) no injection, (II) 0.9% physiological saline injection, (III) ND vaccine injection, and (IV) LAB as an adjuvant for ND vaccine injection. The ND vaccine adjuvanted with LAB significantly increased the daily weight gain, immune organ index, and small intestine histomorphological development in layer chicks while decreasing the feed conversion ratio (FCR). The results suggested that the LAB-adjuvant group significantly affected the relative expression of mucosal mucin protein (mucin-1) and zoccluding small circle protein-1 (ZO-1) (P < 0.05), whereas the relative expression of occludin mRNA was not significantly affected (P > 0.05) compared with the non-injected group. Meanwhile, we indicated that intra-amniotic synbiotic injection significantly maintained the balance of flora (P < 0.05). Compared with the non-injected group, the ND vaccine adjuvanted with the LAB group exhibited significant promotion of the HI and SIgA antibody titers in serum on day 21 (P < 0.05), induction of higher production of cytokines (IL-2, IL-4, IL-6, IFN-γ) in serum. In summary, in ovo injection of ND vaccine adjuvanted with LAB has a positive impact on the growth performance, immune function, and microbiome of growing chicks.

Presence of ginsenoside re during in vitro maturation protects porcine oocytes from heat stress.

Heat stress (HS) affects the development of porcine gametes and embryos negatively, induces the decrease of reproductive ability significantly, threatens global pig production. Ginsenoside Re (GRe), is a main bioactive component of ginseng, shows very specific anti-apoptotic, antioxidant and anti-inflammatory activities. To investigate the alleviating effect of GRe on the in vitro maturation of porcine oocyte under the HS, the polar body extrusion rate, intracellular levels of reactive oxygen species (ROS) and glutathione (GSH), ATP content, mitochondrial membrane potential (MMP) were assessed. For the current study, porcine cumulus-oocyte complexes (COCs) randomly divided into four groups: the control, GRe, HS and HS + GRe group. The results showed that HS inhibited the cumulus cell expansion and polar body extrusion rate, the levels of GSH and MMP, the ATP content, the gene expression of Nrf2 of porcine oocytes and the parthenogenetic activation (PA) embryo development competence, but GRe treatment could partly neutralize these adverse effects. Furthermore, HS increased the ROS formation and percentage of apoptosis, the gene expression of HSP90, CASP3 and CytoC of porcine oocytes, but GRe could weaken the effect on Cyto C and BAX expression induced by HS. Taken together, these results showed that the presence of GRe during in vitro maturation protects porcine oocytes from HS. These findings lay a foundation for GRe may be used as a potential protective drug to protect porcine oocytes against HS damage.

In ovo injection of CHIR-99021 promotes feather follicles development via activating Wnt/ß-catenin signaling pathway during chick embryonic period.

The Wingless-types/beta-catenin (Wnt/ß-catenin) signaling pathway plays an important role in embryonic development and affects the physiological development processes of feather follicles. To investigate the role of Wnt/ß-catenin pathway in regulating feather follicles morphogenesis, in ovo injection of CHIR-99021, an activator of the Wnt/ß-catenin signaling pathway, was conducted in chick embryo model. Initially, a total of 40 embryos were used to assess feather follicles morphogenesis and the expression of ß-catenin (E9-E17). The histological results showed that feather follicle morphogenesis was mainly completed from E9 to E17. ß-catenin was involved in the processing of the appearance of dermal cell condensation (E9) and the completion of the feather follicles morphogenesis (E17). Next, a total of 160 fertilized eggs were randomly divided into 8 groups for in ovo injection at E9, including a Normal Saline injected group (CON) and the 500, 1,000, 2,000, 5,000, 10,000, 50,000, and 100,000 ng CHIR-99021 groups. Dorsal skin tissue samples were collected at E17 for investigating feather follicles morphology and expressions of ß-catenin and lymphoid enhancerbinding factor-1 (LEF1) at gene and protein levels. The results showed that feather follicle diameter in the injected groups were significantly (P < 0.05) increased with limit dose-independence compared to the CON group. CHIR-99021 significantly (P < 0.05) influenced the mRNA expressions of catenin beta-1 (CTNNB1) and downstream target LEF1. In ovo injection of CHIR-99021 caused that ß-catenin and LEF1 were significantly (P < 0.05) increased followed the increased doses as determined by western blotting. The immunochemical results showed that ß-catenin was detected in the dermal papilla of feather follicles. Given these results, this study suggests to developmental biology that in ovo injection of CHIR-99021 promoted feather follicles morphogenesis and development via activating Wnt/ß-catenin signaling pathway and upregulating downstream target LEF1 during embryonic period in chick embryo model. Moreover, CHIR-99021 may be a strong candidate to promote the animal feather/hair industry, especially as a reference for bird feather production.

Chain-ring covalently interconnected cellulose nanofiber/MWCNT aerogel for supercapacitors and sensors.

Bending multi-walled carbon nanotubes (MWCNTs) into rings and structuring them into aerogels is difficult. In this study, cellulose nanofiber (CNF)-MWCNT composite fibers with chain-ring structures were prepared by covalently interconnecting carboxylated CNF and aminated MWCNT by dehydration condensation, solving the problems of the formation of MWCNT aerogels and their phase separation during the compounding process and providing CNF-based aerogels with electrical conductivity. The covalently interconnected aerogels (CAs) had hierarchical porous structures with mechanical resilience and chain-ring fibers, which drove the CNF and MWCNT to form a continuous homogeneous network resulting in a high compression resistance of 269.02 kPa. The CA-based flexible all-solid-state supercapacitor had a quality specific capacitance of 114.8 F g-1, a capacitance retention rate of 94.78% and a Coulomb efficiency of 100%. The CA-based flexible sensor can sense different pressures with a stable response for 1000 cycles. This first study of pulling and bending MWCNT through CNF is expected to inspire more applications of MWCNTs in the fields of flexible supercapacitors and sensors.

Mechanical Properties of Al Foams Subjected to Compression by a Cone-Shaped Indenter.

Indentation tests and numerical simulations were conducted to investigate the effects of the indenter parameters (diameter and cone angle) and the relative density of Aluminum (Al) foams on the deformation mechanism of closed-cell Al foams, load response, and energy-absorbing capability. The results demonstrated that the densification occurred below the indenter, and cell tearing and bending occurred on both sides of the indenter, while the lateral plastic deformation insignificantly took place during the indentation tests. The load response and absorbed energy per unit volume dramatically increased with the cone angle of the indenter and the relative density of Al foams. However, the load response slightly increased but the absorbed energy per unit volume linearly decreased with the diameter of the indenter. Interestingly, the energy-absorption efficiency was independent of the diameter and cone angle of the indenter, and the relative density of Al foams as well. Our results suggest the indentation tests are recommended approaches to reflect the mechanical properties of closed-cell Al foams.

Preparation and Stabilization of High Molecular Weight Poly (acrylonitrile-co-2-methylenesuccinamic acid) for Carbon Fiber Precursor.

Bifunctional comonomer 2-methylenesuccinamic acid (MLA) was designed and synthesized to prepare acrylonitrile copolymer P (AN-co-MLA) using mixed solvent polymerization as a carbon fiber precursor. The effect of monomer feed ratios on the structure and stabilization were characterized by elemental analysis (EA), Fourier transform infrared spectroscopy (FTIR), gel permeation chromatography (GPC), X-ray diffraction (XRD), proton nuclear magnetic (1H NMR), and differential scanning calorimetry (DSC) for the P (AN-co-MLA) copolymers. The results indicated that both the conversion and molecular weight of polymerization reduce gradually when the MLA content is increased in the feed and that bifunctional comonomer MLA possesses a larger reactivity ratio than acrylonitrile (AN). P (AN-co-MLA) shows improved stabilization compared to the PAN homopolymer and poly (acrylonitrile-acrylic acid-methacrylic acid) [P (AN-AA-MA)], showing features such as lower initiation temperature, smaller cyclic activation energy, wider exothermic peak, and a larger stabilization degree, which are due to the ionic cyclization reaction initiated by MLA, confirming that the as-prepared P (AN-co-MLA) is the potential precursor for high-performance carbon fiber.

Effects of in ovo Injection of Astragalus Polysaccharide on the Intestinal Development and Mucosal Immunity in Broiler Chickens.

The purpose of this study was to examine the effects of in ovo injection of Astragalus polysaccharide (APS) on hatchability, body weight (BW), intestinal histomorphology, the number of IgA+ cells and sIgA content in intestine, and the expression of intestinal immune-related genes in broiler chickens. On day 18 of the incubation, a total of 960 live embryo eggs were weighed and randomly divided into 4 treatment groups: a control group and three APS groups. The eggs in the control group were injected with 0.5 mL physiological saline. The eggs in the APS groups were injected with 3 different amounts of APS in 0.5 mL physiological saline: 1 mg (APSL), 2 mg (APSM) and 4 mg (APSH). The solution was injected into the amnion of each egg. The results showed that in ovo injection of APS did not affect the hatchability but increased the body weight of the 14 d and 21 d chickens, with a significant increase observed in the APSM group (P < 0.05). At most time points, the villus height (VH) was increased (P < 0.05) and the crypt depth (CD) was decreased (P < 0.05) in the small intestine of the broilers, with higher VH/CD ratios in the APSL and APSM groups compared with the control group. The number of IgA+ cells in the mucosa and the secretory immunoglobulin A (sIgA) levels in the intestinal washings were higher in the APSM and APSH groups than in the APSL and control groups. The gene expression levels of interleukin (IL)-2, interleukin (IL)-4, interferon gamma (IFN-γ), and Toll-like receptor (TLR)-4 were significantly enhanced by APS stimulation at most time points (P < 0.05). These results indicated that in ovo injection of APS has the potential of promoting intestinal development and enhancing intestinal mucosal immunity of broiler chickens in the early stage after hatching.

The construction of recombinant Lactobacillus casei expressing hemagglutinin-neuraminidase protein and its immune response in chickens.

Newcastle disease virus (NDV) is one of the most important diseases in poultry. The present study generated recombinant surface-displayed Lactobacillus casei (L. casei) expressing the hemagglutinin-neuraminidase (HN) of NDV (Lc-pPG-HN) and a live pPG vector (Lc-pPG) and evaluated their immunogenicity. A 1670 bp HN gene fragment was successfully amplified and cloned into a prokaryotic protein expression system. Protein expression in the resulting recombinant Lc-pPG-HN (surface displayed) strain was verified using Western blotting and indirect immunofluorescence. A single band was observed on the Western blots, and the molecular weight of the corresponding protein was 63 kDa. A fluorescent signal for Lc-pPG-HN was observed using fluorescence microscopy. A total of 270 healthy chicks were divided into three treatment groups. Five replicates were used for each treatment, while six chicks were used per replicate. The following three treatment groups were used: physiological saline group (Control), Lc-pPG group and recombinant vaccine group (Lc-pPG-HN). The primary immunization and booster immunization of the chicks were performed via oral administration on 1 and 10 days old. Tissue and blood samples were collected from chickens that received oral recombinant L. casei strains on 1, 7, 14 and 21 days post-immunization for immune-related index analyses. Chickens orally immunized with Lc-pPG-HN showed significantly increased body weights and immune organ indices. Oral immunization with Lc-pPG-HN also enhanced the concentrations of serum interleukin-2 (IL-2), interferon-γ (IFN-γ), intestinal lavage fluid secretory immunoglobulin A (SIgA) and histomorphological development of the small intestine. Our results also indicated that recombinant L. casei significantly increased Lactobacillus and Bifidobacterium colonization and decreased the relative abundance of Escherichia coli (E. coli) in the chicken caecum. Similar enhancement effects from hemagglutination inhibition were also observed in the antibody titers. Oral administration of Lc-pPG-HN effectively protected against NDV and alleviated the symptoms of the NDV challenge. In summary, recombinant L. casei had positive impacts on the performance, immunological function, gut development, and microbiota of growing chicks and may be a potential therapeutic candidate against NDV.

The Effects of In Ovo Injection of Synbiotics on the Early Growth Performance and Intestinal Health of Chicks.

In this study, the effects of synbiotic inclusion at the intra-amniotic stage in layer chicks were evaluated with different parameters, such as performance, immunological function, intestinal development, and cecal microflora content. A total of 1,200 eggs with fertile embryos were allocated into four treatment groups. For every treatment, five replicates were used, and 60 eggs were included in each replicate. The following four treatment groups were established: the non-injected group, 0.9% physiological saline injection (saline) group, 1 × 106 CFU/egg Lactobacillus plantarum injection (probiotic) group, and 1 × 106 CFU/egg L. plantarum + 2 mg/egg Astragalus polysaccharide injection (synbiotic) group. In ovo injection was carried out at 18.5 days of incubation. The results showed that in ovo injection of probiotics or synbiotics did not affect the hatching or growth performance of the chicks but significantly increased their feed intake (FI), body weight (BW), and the feed conversion ratio (FCR). Additionally, in ovo injection of synbiotics enhanced the levels of serum interleukin-2 (IL-2), interferon-γ (IFN-γ), and secretory immunoglobulin A (SIgA) in intestinal lavage fluid and the histomorphological development of the small intestine. Our results also indicated that intra-amniotic synbiotic injection significantly increased Lactobacillus and Bifidobacterium colonization while decreasing the relative abundance of Escherichia coli in the chicken cecum (P < 0.05). In summary, in ovo injection of synbiotics had positive impacts on the performance, immunological function, gut development, and microbiota of growing chicks.

Immunomodulatory effect of Acanthopanax senticosus polysaccharide on immunosuppressed chickens.

The immunomodulatory effect of Acanthopanax senticosus polysaccharide (ASPS) on immunosuppressed chickens induced by cyclophosphamide (Cy) was observed in this study. Four hundred 7-day-old chickens were randomly divided into 4 groups: vaccinated control group (VC group), Cy-challenged control group (Cy group), Cy-challenged + low-dose ASPS group (ASPSL + Cy group), and Cy-challenged + high-dose ASPS group (ASPSH + Cy group). All groups except the VC group were injected with Cy at a dose of 80 mg/kg/day of BW for 3 successive days to induce immunosuppression. At the age of 10 d, the ASPSL + Cy group and ASPSH + Cy group were intramuscularly injected with 0.2 mL of ASPS at the dose of 100 and 200 mg/mL/day, respectively, once a day for 3 successive days. The Cy group was injected with saline solution in the same way as the 2 ASPS groups. At the age of 14 d, the chickens were vaccinated with Newcastle disease (ND) vaccine in all groups. On day 7, 14, 21, and 28 after the vaccination, BW, lymphocyte proliferation, the serum antibody titers of the ND vaccine, the proportion of CD4+ and CD8+ T lymphocytes, and the concentrations of interferon gamma and IL-2 were determined. The results showed that chickens were injected with Cy at a dose of 80 mg/kg of BW for 3 d displayed lower immune responses than the control group, indicating that the immunosuppressive model was successfully established. At most time points, both high and low doses of ASPS could significantly promote lymphocyte proliferation; enhance BW, antibody titers, and the proportion of CD4+ and CD8+ T lymphocytes; and raised the concentrations of interferon gamma and IL-2 in Cy-treated chickens compared with those in the Cy control group (P < 0.05). These results indicated that ASPS could resist immunosuppression induced by Cy and may be a new-type immune adjuvant to improve vaccination in normal and immunosuppressed chickens.

The immune adjuvant effect of Astragalus polysaccharide on in ovo injection of Newcastle disease vaccine.

In this study, immunogenic efficacies of in ovo administration of Astragalus polysaccharide (APS) along with live Newcastle disease vaccine (live ND vaccine) (live VG/GA strain) were evaluated. Four hundred fertilized eggs were randomly divided into four groups (n = 100/group), and vaccinated in ovo, respectively, with solutions of APS, live ND vaccine, live ND vaccine combined with APS, and 0.9% physiological saline into their amniotic fluid on d 18.5 of incubation. Significant improvement of chicks' development was displayed in those vaccinated with live ND vaccine adjuvanted with APS in ovo, manifested as enhanced hatchability and gaining weight. Moreover, in ovo administration of live NDV vaccine plus APS could significantly enhance the serum anti-NDV antibody titres and interferon gamma (IFN-γ), interleukin (IL)-2, IL-4 and IL-6 concentrations, promote lymphocyte proliferative capability as well as improve the frequencies of CD4+ and CD8+ T cells in peripheral blood. Overall results indicated in ovo administration of live ND vaccine adjuvanted with APS could stimulate stronger humoral and cellular responses in newly hatched chicks.

Photodynamic therapy in the treatment of xeroderma pigmentosum: A case report.

Xeroderma pigmentosum (XP) is a rare autosomal recessive dermatosis that is often complicated by multiple skin tumours at exposed locations, which are difficult to treat. We report a case of a 12-year-old girl with XP treated with oral retinoic acid and photodynamic therapy (PDT) with good clinical results. She had an 8-year history of multiple skin lesions that first appeared on her nasal dorsum, but gradually increased in size and spread to her entire face, neck, and upper limbs. Notably, the lesions became evidently aggravated after sun exposure. When she was 6 years old, sesame-seed-sized papules and plaques appeared, which were fragile and irregular in shape and would self-rupture, accompanied with slight itchiness and bloody exudate. Examination revealed multiple basal cell carcinomas. The tumours were treated with local carbon dioxide laser therapy combined with PDT. On the follow-up visit 2 months after the surgery, most of the skin lesions on her face had subsided. In cases of multiple tumours, PDT can be the treatment method of choice because it is less invasive, has less side effects, and does not damage the surrounding normal tissues.

Construction and immune efficacy of recombinant Lactobacillus casei strains expressing Malt from Aeromonas veronii.

Aeromonas veronii is an important zoonotic pathogen that causes significant economic losses in the aquaculture industry. The use of probiotics in aquaculture is a practical alternative to antibiotics to promote animal health and aid in disease prevention. In the present study, we aimed to construct a recombinant Lactobacillus casei(surface-displayed or secretory) strain containing Malt from A. veronii TH0426 and assess its potential as an oral vaccine. A 1314-bp Malt gene fragment was successfully amplified and cloned into a prokaryotic protein expression system. Protein expression in resulting recombinant strains Lc-MCS-Malt (surface-displayed) and Lc-pPG-Malt (secretory) was then verified by Western blotting and indirect immunofluorescence. A single band was observed on the Western blots, with the molecular weight of the corresponding protein shown to be 48 kDa. Furthermore, a fluorescent signal for Lc-MCS-Malt was observed by fluorescence microscopy. At 0, 7, 16, 25, and 34 days post-immunization, tissue and blood samples were collected from common carp orally administered with the recombinant L. casei strains for immune-related index analyses. Treatment of common carp with the recombinant vaccine candidate stimulated high serum or skin mucus specific antibody titers and induced a higher lysozyme, ACP, SOD activity, while fish fed with Lc-pPG or PBS had no detectable immobilizing immune responses. Expression of IL-10, IL-1ß, TNF-α, and IFN-γ genes in the group immunized with recombinant L. casei were significantly (P < 0.05) up regulated as compared with control groups, indicating that inflammatory response and cell immune response were triggered. Results also showed that recombinant L. casei could stimulate the mucosa through colonization of the intestine, resulting in increased transcription of IL-10, IL-1ß, TNF-α, and IFN-γ. Immunity and colonization assays also showed that after 34 days of fasting, recombinant L. casei were still present in the intestines of the immunized fish. Common carp that received Lc-MCS-Malt(53.3%) and Lc-pPG-Malt (46.7%) exhibited higher survival rates than the controls after challenge with the pathogen A. veronii. Our findings suggested that recombinant L. casei can adequately protect fish and improve immunity, providing a theoretical basis for the future development of an oral Lactobacillus vaccine for use in aquaculture.

Functional analysis of hisJ in Aeromonas veronii reveals a key role in virulence.

Aeromonas veronii is an important aquatic zoonotic pathogen in humans and animals. In recent years, extracellular proteins from bacteria have been found to be the major pathogenic factors for aquatic animals. The aim of this study was to systematically analyze the extracellular proteins of nine sources of A. veronii and the effects of hisJ on virulence. We screened only the common proteins from nine different sources of A. veronii by liquid chromatography-tandem mass spectrometry and identified the gene hisJ. We then constructed ΔhisJ (deleted) and C-hisJ (complemented) variants of A. veronii TH0426 to assess the biological function of hisJ. While the ΔhisJ strain did not show altered growth (P > 0.05), we observed that it had reduced colony formation and biofilm formation and reduced adhesion to and invasion of epithelioma papulosum cyprini cells by 2.0-, 1.9-, and 10.8-fold, respectively. Additionally, infection experiments on zebrafish and mouse infection experiments showed that the virulence of the ΔhisJ strain was decreased by 865-fold (P < 0.001) compared with the wild-type strain; virulence of the complemented C-hisJ strain was reduced only 2.8-fold. Furthermore, in the context of hisJ deletion, flagella of A. veronii TH0426 were easily detached and the expression of virulence genes was downregulated. A persistence test (of bacterial colonies in crucian carp) showed that the number of bacteria in the immune organs of the ΔhisJ-infected group was lower than that in the wild-type-infected group. Overall, these results show that hisJ affects flagellar shedding, virulence, biofilm formation, adhesion, and invasion of A. veronii TH0426, and that hisJ is closely associated with virulence and plays a crucial role in its pathogenicity of A. veronii TH0426.

Three-Dimensional Hierarchically Porous Graphene Fiber-Shaped Supercapacitors with High Specific Capacitance and Rate Capability.

Chemically converted graphene fiber-shaped supercapacitors (FSSCs) are highly promising flexible energy storage devices for wearable electronics. However, the ultralow specific capacitance and poor rate performance severely hamper their practical applications. They are caused by severe stacking of graphene nanosheets and tortuous ion diffusion path in graphene-based electrodes; thus, the ultralow utilization of graphene has been rarely carefully considered to date. Here, we address these issues by developing three-dimensional hierarchically porous graphene fiber with the incorporation of holey graphene for efficient utilization of graphene to achieve fast charge diffusion and good charge storage capability. Without deterioration in electrical but robust mechanical properties, the optimal graphene fiber shows ultrahigh specific capacitance of 220.1 F cm-3 at current density of 0.1 A cm-3 and boosted specific capacitance of 254.3 F cm-3 at 0.1 A cm-3 after nitrogen doping. Moreover, the nitrogen-doped 40% holey graphene hybrid fiber-assembled FSSC exhibits ultrahigh rate capability (96, 91, and 87% at current density of 0.5, 1.0, and 2.0 A cm-3, respectively, and 67% even at ultrahigh current density of 10.0 A cm-3) and excellent cycle stability (95.65% capacitance retention after 10 000 cycles). The contribution of three-dimensional interconnected hierarchically porous network to the enhanced electrochemical (EC) performance is semiquantitatively elucidated by Brunauer-Emmett-Teller and energy dispersive spectroscopy mapping. Our work gives insights into the importance of fully utilizing graphene and provides an efficient strategy for high EC performance in chemically converted graphene-based FSSCs.

Structure based optical properties and catalytic activities of hydrothermally prepared CuS nanostructures.

The nano-sized copper sulfides (CuS) with different morphologies were prepared by hydrothermal method without any surfactant or template. The morphology and structure of CuS were characterized by powder x-ray diffraction (XRD), Fourier transform infrared spectroscopy, x-ray photoelectron spectra (XPS), field emission scanning electron microscopy (FESEM), high-resolution transmission electron microscopy (HRTEM), Brunauer-Emmett-Teller (BET) and ultraviolet-visible (UV-vis) absorption spectroscopy. FESEM results show that four morphologies of CuS (flower-like nanospheres, cross-linked nanodisks, cross-linked nanoplates and nanosheets) were prepared simply by changing the hydrothermal solvent. According to the XPS, XRD and HRTEM results the synthesized nano-sized structures are highly crystallized pure hexagonal covellite CuS. UV-vis spectra results show intense absorption peaks in the visible region, confirming that the resultant CuS has potential application in the field of solar cells. The catalytic activities of resultant CuS on model pollutant methylene blue (MB) in the dark were also investigated in detail. The small and flat crystallites show rapid degradation rate on MB, which is attributed to the numerous active sites on their large specific surface area. The as-synthesized CuS nanosheets took the shortest time (only 15 min) to degrade MB completely compared with the other nanostructural CuS in this work as well as previously reported ones. Total organic carbon removal of the samples approved mineralization of the MB pollutant. Thus, CuS is an excellent catalyst for degrading organic pollutants, which does not require light energy for its catalytic activities.