酸酶复合法提取鲢鱼鱼鳞胶原蛋白的工艺研究

以鲢鱼鱼鳞为研究对象,采用酸酶复合法提取鱼鳞胶原蛋白,并对酶法提取工艺中的酶量、时间、料液比等因素进行单因素试验和正交优化。使用氨基酸自动分析仪、聚丙烯酰胺凝胶电泳(SDS-PAGE)和圆二色谱(CD)对酸溶胶原蛋白(ASC)和酶溶胶原蛋白(PSC)的性质进行研究。试验表明,酸提取后的残渣进行酶提取,其最佳工艺条件为:酶量4%,料液比1∶25,提取时间60 h。ASC提取率达到5.09%,PSC提取率最高达到12.06%,胶原蛋白总提取率为17.15%。氨基酸组成结果表明,ASC和PSC均为典型的I型胶原蛋白;SDS-PAGE电泳分析显示,ASC和PSC的电泳区带与I型胶原蛋白标准品基本一致;CD显示ASC和PSC均保持三股螺旋结构。     

Inkjet Printed Disposable High-Rate On-Paper Microsupercapacitors

On-paper microsupercapacitors (MSCs) are a key energy storage component for disposable electronics that are anticipated to essentially address the increasing global concern of electronic waste. However, nearly none of the present on-paper MSCs combine eco-friendliness with high electrochemical performance (especially the rate capacity). In this work, highly reliable conductive inks based on the ternary composite of poly(3,4-ethylenedioxythiophene): poly(styrenesulfonate) (PEDOT:PSS), graphene quantum dots and graphene are developed for scalable inkjet printing of compact (footprint area ≈ 20 mm²) disposable MSCs on commercial paper substrates. Without any post treatment, the printed patterns attain a sheet resistance as low as 4 Ω ?^?1. The metal-free all-solid-state MSCs exhibit a maximum areal capacitance > 2 mF cm^?2 at a high scan rate of 1000 mV s^?1, long cycle life (>95% capacitance retention after 10 000 cycles), excellent flexibility, and long service time. Remarkably, the “totally metal-free” MSC arrays are fully inkjet printed on paper substrates and also exhibit high rate performance. The life cycle assessment indicates that these printed devices have much lower eco-toxicity and global warming potential than other on-paper MSCs.     

Shungite/poly(vinyl alcohol) hybrid hydrogels: An efficient adsorption material for rare earth metals in aqueous media

Rare earth elements play a pivotal role in modern technologies, thereby driving an escalating demand for their procurement. To effectively extract these elements from aqueous solutions, it is imperative to explore innovative sorbent materials. In this context, a hydrogel sorbent material was developed by employing poly(vinyl alcohol) (PVA) and shungite—an economical, naturally occurring, easily processable, and sustainable material. This was achieved through the freezing–thawing method, employing sodium borate as a crosslinking agent. The physicochemical characteristics of the hydrogels were determined through scanning electron microscopy (SEM), transmission electron microscopy (TEM), thermogravimetric analysis (TGA), Fourier-transform infrared spectroscopy (FTIR), Brunauer–Emmett–Teller (BET) analysis, Zetasizer analysis, and elemental analysis. The shungite-incorporated PVA hydrogels displayed notable characteristics, including a substantial swelling capacity of 61% and a specific surface area of 32.8 m²/g. Most significantly, these hydrogels exhibited a remarkable affinity for La³⁺ ions, with an uptake ratio of 134 mg/g. This was followed by Nd³⁺, Dy³⁺, and Er³⁺ ions, which displayed uptake ratios of 79, 74, and 73 mg/g, respectively.     

Design of piezoelectric nanogenerator based on BiFeO3/epoxy resin with potential application for wearable electronic devices

Growing demand for electric energy in newly developed electronic systems causes increasing interest in research on piezoelectric nanogenerators (PENGs). Design and fabrication of such devices is challenging, considering cost of materials used in their construction. This is the main reason why intensive research has begun on 0-3 composites with piezoelectric properties. One of the most promising constituent materials for composites fabrication are polymers, due to their low cost and easy processing. Herein, we present fabricated wearable PENG with good impact and vibration energy conversion properties. Correlation between matrix stiffness and piezoelectric properties of 0-3 type composite is proposed. It was found that composite with 10 wt.% of BiFeO₃ particles exhibits power output density for vibrations, finger tapping, and air stream pressure P = 11.12 nW cm⁻³, P = 4.83 μW cm⁻³, and P = 769.2 μW cm⁻³, respectively. Decrease in stiffness of epoxy matrix results at least in two-times lower power output density for this same PENG. The obtained results demonstrate that the fabricated BFO/epoxy composites show the wide applicability and potential to be integrated with other functional devices, for example, as a part of wearable devices in smart shoes.     

Effect of Co-Mo catalyst preparation and CH4/H2 flow on carbon nanotube synthesis

Abstract

Supported Co-Mo catalysts with a given ratio of metals were prepared from polyoxomolybdate Mo₁₂O₂₈(μ₂-OH)₁₂{Со(H₂O)₃}₄ using impregnation and combustion methods. Effects of the type of catalyst and the ratio and flow of methane and hydrogen gases on the structure of carbon nanotubes (CNTs) synthesized by catalytic chemical vapor deposition (CCVD) method were studied using transmission electron microscopy and Raman spectroscopy. The catalyst prepared by combustion method yielded mainly individualized CNTs, while the CNTs were highly entangled or bundled when impregnation method was used. In both cases, addition of hydrogen to methane led to reduction of the CNT yield. The samples synthesized using two different catalysts and the same CH₄/H₂ ratio and flow of gases were tested in electrochemical capacitors. A higher specific surface area of the CNTs grown over impregnation-prepared catalyst caused a better performance at scan rates from 2 to 1000?mV/s.     

Fibrillar Elastomeric Micropatterns Create Tunable Adhesion Even to Rough Surfaces

Biologically inspired, fibrillar dry adhesives continue to attract much attention as they are instrumental for emerging applications and technologies. To date, the adhesion of micropatterned gecko‐inspired surfaces has predominantly been tested on stiff, smooth substrates. However, all natural and almost all artificial surfaces have roughnesses on one or more different length scales. In the present approach, micropillar‐patterned PDMS surfaces with superior adhesion to glass substrates with different roughnesses are designed and analyzed. The results reveal for the first time adhesive and nonadhesive states depending on the micropillar geometry relative to the surface roughness profile. The data obtained further demonstrate that, in the adhesive regime, fibrillar gecko‐inspired adhesive structures can be used with advantage on rough surfaces; this finding may open up new applications in the fields of robotics, biomedicine, and space exploration.     

Hematopoietic Disorders,Renal Impairment and Growth in Mucopolysaccharidosis-Plus Syndrome

Mucopolysaccharidoses (MPS) are rare lysosomal storage disorders (LSD) characterized by the excessive accumulation of glycosaminoglycans (GAG). Conventional MPS, caused by inborn deficiencies of lysosomal enzymes involved in GAG degradation, display various multisystemic symptoms—including progressive neurological complications, ophthalmological disorders, hearing loss, gastrointestinal and hepatobiliary issues, cardiorespiratory problems, bone and joint abnormalities, dwarfism, and coarse facial features. Mucopolysaccharidosis-Plus Syndrome (MPSPS), an autosomal recessive disease caused by a mutation in the endo-lysosomal tethering protein VPS33A, shows additional renal and hematopoietic abnormalities (“Plus symptoms”) uncommon in conventional MPS. Here, we analyze data from biochemical, histological, and physical examinations—particularly of blood counts and kidney function—to further characterize the clinical phenotype of MPSPS. A series of blood tests indicate hematopoietic symptoms including progressive anemia and thrombocytopenia, which correlate with histological observations of hypoplastic bone marrow. High urinary excretion of protein (caused by impairments in renal filtration), hypoalbuminemia, and elevated levels of creatinine, cholesterol, and uric acid indicate renal dysfunction. Histological analyses of MPSPS kidneys similarly suggest the extensive destruction of glomerular structures by foamy podocytes. Height and weight did not significantly deviate from the average, but in some cases, growth began to decline at around six months or one year of age.