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Transition metal oxides (TMOs) have excellent electrochemical properties. However, they are commonly associated with short cycle lives, agglomeration, and lower electrical conductivity. To ameliorate these drawbacks, porous rod-shaped CuO@Co3O4 has been synthesized through calcination with optimized oxidation temperature by using CuCo-MOF-74 as a template. Due to the porous structure, the CuO@Co3O4 electrode significantly increases the contact area with the electrolyte and greatly improves the reaction kinetics. As a result, the CuO@Co3O4 electrode exhibits excellent electrochemical performance with a specific capacitance of 545.5 F g−1 at a current density of 1 A g−1. The capacitance retention at 10 A g−1 was 88.7% after 10 000 cycles. Furthermore, an asymmetric supercapacitor (SC) has been assembled with CuO@Co3O4 as the positive electrode and commercial reduced graphene oxide (RGO) as the negative electrode, and the device has exhibited an energy density of 38.2 W h kg−1 at a power density of 1268.3 W kg−1. Impressively, the capacitance retention remained 83.2% even after 10 000 cycles at a high current density of 10 A g−1. This performance has demonstrated the potential of CuO@Co3O4 as an anode material for SCs. [ABSTRACT FROM AUTHOR]

In order to study the failure mechanism of high-voltage cable buffer layer caused by moisture and the performance of the material after immersion and drying, according to the structure and size of 110 kV XLPE cable, the requirements for the separation distance between corrugated aluminum sheath and insulating outer shield before and after the change of buffer layer resistivity caused by moisture were calculated, the influence of moisture on ablation failure was analyzed. The test platform of buffer layer material was built, the properties of two kinds of materials without water immersion and after water immersion drying were tested, including semi-conductive buffer water-blocking tape and semi-conductive buffer tape. The results show that when the moisture content was large, the resistivity of the buffer layer increases, which reduces the requirements of the allowable separation distance of the cable, and was more likely to cause the discharge and ablation of the buffer layer. The water in the buffer layer was removed by drying at 70 °C, with thickness, weight, the water content, elongation at break, breaking strength and volume resistivity can be recovered, which verifies that the heating drying method is feasible for the removal of water from the buffer layer.

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Microbial treatment of natural fibers is a preferred alternatives in ramie degumming process as compared to conventional chemical degumming technology with alkaline treatment at high temperature. Usually, it is difficult to degrade the noncellulosic components of ramie bast completely with a single strain in the mono-culturing degumming system. Microbial coculture strategy has been widely used in biotechnology, especially in the degradation of biological materials. In the present study, five strains for ramie degumming were identified as Dickeya dadantii strain DCE-01, Bacillus subtilis strain 1101, Bacillus sp. B6, Bacillus cereus strain B7, and Bacillus cereus strain B8 by sequencing of 16 S rRNA genes. Enzymatic activities characterization, ramie degumming experiments with mono-culturing systems, and the evaluation of strain compatibility showed that group DCE-01/B7 were the most suitable pairs for the construction of bacterial coculturing system. After preliminary optimization of coculturing fermentation condition, the weight loss weight ratio of ramie fibers was 27%, which was increased 13.6% and 8.9% while compared to mono-culturing systems of strain B7 and DCE-01 respectively. These data highlighted the benefit of microbial coculture strategy in the application of ramie degumming process, and indicated a higher-efficiency alternative for the microbial degumming in the textile industry. [ABSTRACT FROM AUTHOR]

Atypical meningioma is a specific type of meningioma that is relatively rare in clinical practice. The clinical manifestations of atypical meningioma are non-specific and the imaging findings are similar to those for other intraspinal space-occupying lesions. It is usually misdiagnosed as schwannoma or metastases, and it is necessary to rely on intraoperative findings and pathological examination to confirm the diagnosis. Atypical meningioma invading the intervertebral foramen and causing bone destruction is rare. The present study describes the case of a patient with cervical intraspinal atypical meningioma combined with cervical bone destruction. A 50-year-old female patient presented with numbness of the extremities with unstable walking, and underwent magnetic resonance imaging (MRI) of the cervical spine. MRI showed a space-occupying lesion in the spinal canal at the C2-4 level. The patient underwent cervical intraspinal lesion resection, and postoperative pathology confirmed atypical meningioma (World Health Organization grade II). The patient received dehydration and hormone therapy, and was discharged after the symptoms improved. Radiotherapy was performed 2 months after discharge. Cervical MRI 3 months after the operation showed that the tumor resection was satisfactory. To the best of our knowledge, the present study is the first to report on this specific type of meningioma. The present case report may provide useful information for clinicians to diagnose and treat the disease. [ABSTRACT FROM AUTHOR]

Degumming is the most important step before kenaf bast fibers used in textile industry. Microbial degumming is an environmental protection and energy-saving technology to replace the conventional chemical degumming. Higher efficiency strains are the essential prerequisite to promote the application of microbial degumming technology. Generally, the screening and evaluation of strains for kenaf bast degumming were based on activity of functional enzymes produced by microorganism. In order to investigate the relationship between enzymatic activity and effect of kenaf bast degumming, strains DCE-01, 1101, B6, B7, and B8 were incubated in pure cultured, sterilized and non-sterilized degumming systems. After culturing for 16 h, functional enzymes for kenaf bast degumming (such as pectinase, neutral protease, xylanase, β-mannanase, laccase, lignin peroxidase and manganese peroxidase) were detected in the supernatant, and degumming effect of kenaf bast under sterilized and non-sterilized systems were evaluated respectively. Results revealed that strain DCE-01 was the best for kenaf bast degumming, though its enzymatic activity was not the highest among five strains. And the pretreatment of kenaf bast by high-pressure-steam sterilization could promote the degumming effect. This study suggested that there were limitations when screening or evaluating high-efficient strains for kenaf bast degumming with the guidance of enzymatic activity. [ABSTRACT FROM AUTHOR]

To explore high-quality microbial resources with the capability of ramie degumming, we collected soil samples from rotten ramie and straw heaps. After enrichment culture by ramie raw materials, bacterial strains with the potential ramie-degumming function were screened using a pectin-hydrolysis plate. Dominant bacteria were identified by combining colonial morphological characteristics with the molecular biology method, and their ramie-degumming effects were verified through comprehensive biological degumming indices. Results demonstrated that Bacillus aryabhattai, Bacillus thuringiensis, Lysinibacillus fusiformis, and Acidovorax temperans were successfully obtained. The highest pectinase activity, 98.2 U/mg, was found by A. temperans. B. thuringiensis showed the best ramie-degumming effect. The residual gum content, single-fiber linear density, and bundle-breaking strength of the degummed ramie fiber treated with B. thuringiensis were 8.32%, 6.80 dtex, and 7.84 cN/dtex, respectively. The residual gum content of the ramie fiber treated with B. thuringiensis met the textile requirement (<10%), and the values of all other indicators were also satisfactory. Therefore, B. thuringiensis was an excellent strain for ramie degumming, indicating potential industrial applications. [ABSTRACT FROM AUTHOR]

Ramie (Boehmeria nivea L.), a perennial herb, is an important bast fiber plant. Its fiber with the advantages of attractive luster, high tenacity, enhanced strength, and good microbial resistivity is well known as the queen of natural fibers. The abundant cellulose fibers in ramie raw materials are stuck tightly by gums consisting of pectic substances, hemicelluloses, and little lignin. The gum should remove from the ramie raw material through degumming process to separate fibers, unveil unique fiber properties, and improve fiber-spinning ability to fulfill textile requirements. Low degumming efficiency and high environmental pollution are the major problems hindering the utilization of ramie fibers. Ramie degumming involves the degradation of pectin and hemicelluloses, which requires chemical, physical, biological treatment, or a combination of several treatments. No stereotyped parameters of the given degumming method have been yet established for the extraction of textile-grade ramie fibers. This review evaluated integrated methodology involving chemical, physical, biological and biochemical methods to degum raw ramie and obtain textile-grade refined fibers. [ABSTRACT FROM AUTHOR]