Sorghum as Dry Land Feedstock for Fuel Ethanol Production

Dry land crops such as sorghums （grain sorghum, promising feedstocks for fuel ethanol production. The major issue sweet sorghum and forage sorghum） have been identified as for using the sweet sorghum as feedstock is its stability at room temperature. At room temperature, the sweet sorghum juice could lose from 40% to 50% of its fermentable sugars from 7 to 14 days No significant sugar content and profile changes were observed in juice stored at refrigerator temperature in two weeks. Ethanol fermentation efficiencies of fresh and frozen juice were high （-93%）. Concentrated juice （≥25% sugar） had significantly lower efficiencies and large amounts of fructose left in finished beer; however, winery yeast strains and novel fermentation techniques may solve these problems. The ethanol yield from sorghum grain increased as starch content increased. No linear relationship between starch content and fermentation efficiency was found. Key factors affecting the ethanol fermentation efficiency of sorghum include starches and protein digestibility, amylose-lipid complexes, tannin content, and mash viscosity. Life cycle analysis showed a positive net energy value （NEV） = 25 500 Btu/gal ethanol. Fourier transform infrared （FTIR） spectroscopy and X-ray diffraction （XRD） were used to determine changes in the structure and chemical composition of sorghum biomasses. Dilute sulfuric acid pretreatment was effective in removing the hemicellulose from biomasses and exposing the cellulose for enzymatic hydrolysis. Forage sorghum lignin had a lower syringyl/guaiacyl ratio and its pretreated biomass was easier to hydrolyze. Up to 72% hexose yield and 94% pentose yield were obtained by using a modified steam explosion with 2% sulfuric acid at 140℃ for 30 min and enzymatic hydrolysis with cellulase.

Exploring hemp seed hull biomass for an integrated C-5 biorefinery:Xylose and activated carbon

Large quantities of hemp hulls can be completely utilized for creation of value-added products (cost effective biofuels and biochemicals) through a biorefinery approach. A sustainable approach in making xylose, a low calorie sweetener and high surface area activated carbons (AC) for super capacitors, attracts interest. The AC when leveraged as a co-product from biorefinery process makes it more cost effective and, in this paper, we discuss the production of xylose and AC from hemp seed hull with methane sulphonic acid (MSA) hydrolysis. Xylose recovery with MSA hydrolysis was 25.15 g/L when compared to the traditional sulphuric acid (SA) hydrolysis of 19.96 g/L at the same acid loading of 1.8 %. The scanning electron microscope (SEM) images and Fourier transform infrared (FT-IR) spectra indicate partial delignification along with hemicellulose hydrolysis responsible for high xylose recovery. Post hydrolysis fibers were KOH activated and carbonized to make AC. The MSA hydrolyzed and KOH activated fiber produced pure, fluffier and finer particle AC with a drastic increase in surface area 1 452 m2/g when compared to SA hydrolyzed of 977 m2/g. These results indicate the potential of MSA in dilute acid hydrolysis of biomass for xylose recovery and production of high surface area activated carbon. From a production standpoint this can lead to increased use of sustainable low-cost agricultural biomass for making high surface area AC as components in supercapacitors.

Universal probe with oriented antibody to improve the immunochromatographic assay of lead ions in Procambarus clarkii

Objectives:Based on the information from the random inspection of foods by the China Food and Drug Administration in 2022,the contamin-ation levels of lead ions are high in many edible products.Traditional methods of detecting lead ions cannot meet the requirements of on-site analysis of food due to the need for large equipment.The immunochromatographic assay(iCA)is an effective,rapid,on-site analytical technique for determining lead ions in foods.However,the performance of ICA based on the traditional probe(AuNP-mAb)is limited by ignoring the influ-ence of theantibody orientation.Materials and Methods:In this study,we developed an efficient technology for constructing a universal probe(AuNP-PrA-mAb)based on the oriented immobilization of antibody.The performance of ICA was largely improved due to specific binding of the Fc region of the antibody with recombinant protein A(PrA)on the surface of a gold nanoparticle(AuNP).The ICA based on a universal probe was applied for the qualitative and quantitative detection of lead ions in Procambarus clarki within 30 min.Meanwhile,a simple and fast pretreatment method based on dilute acid extraction was developed forpretreating thePclarkii containing leadions.Results:The visual limit of detection and the scanning limit of quantization of the developed iCA strip for lead ions were O.5 ng/mL and 0.28 ng/mL,respectively.The sensitivity of ICA based on universal probe was 10-fold higher than that of the ICA using traditional probe.Furthermore,the detection results had no obvious difference between the ICA and ICP-MS with t-test statistical method.Conclusions:The developed ICA based on a universal probe presented broad application prospects in detecting contaminants in foods.

OFHC copper substrates for niobium sputtering:comparison of chemical etching recipes

Purpose Niobium sputtered on copper has been a popular alternative approach for superconducting radio frequency(SRF)community in the last few decades.Comparing to bulk materials of a few millimeters,high-purity niobium of merely a few microns is sufficient to realize superconductivity on the coated surface.Being niobium thin film,it has been widely acknowledged that surface quality of the substrate plays a vital role in obtaining a superior niobium coating with excellent SRF performance.Therefore,proper chemical treatment of the substrate before coating is crucial and the ultimate goal is to create a smooth and defect-free surface.Prior to the design of a cavity etching system,the mechanism of SUBU as well as two industry-used solutions is studied in detail on samples.Methods Copper samples were first pre-treated by mechanical grinding to remove fabrication damages,obvious defects and visible impurities.Two chemical solutions widely used in industries were subsequently chosen to etch the samples.Finally,the established SUBU solution was used independently on these pre-treated samples for comparison.Surface morphology and etching rate were measured accordingly.Results and conclusions Mirror-like copper surface was created by using the SUBU solution thus qualified for subsequent niobium sputtering,while the other two solutions used in industries were less effective with nonideal surface morphology.The chemical reactions,the experimental requisites and the involved processes are extensively elucidated for all three solutions.Limitations for SUBU were examined,and the optimum ratio of the chemical bath volume to sample surface area was also determined.These investigations will serve as an important guidance for the development of a chemical etching system for elliptical copper cavities.

Study of simultaneous saccharification and fermentation for steam exploded wheat straw to ethanol

Although simultaneous saccharification and fermentation(SSF)has been investigated extensively,the optimum condition for SSF of wheat straw has not yet been determined.Dilute sulfuric acid impregnated and steam explosion pretreated wheat straw was used as a substrate for the production of ethanol by SSF through orthogonal experiment design in this study.Cellulase mixture(Celluclast 1.5 1 and β-glucosidase Novozym 188)were adopted in combination with the yeast Saccharomyces cerevisiae AS2.1.The effects of reaction temperature,substrate concentration,initial fermentation liquid pH value and enzyme loading were evaluated and the SSF conditions were optimized.The ranking,from high to low,of influential extent of the SSF affecting factors to ethanol concentration and yield was substrate concentration,enzyme loading,initial fermentation liquid pH value and reaction temperature,respectively.The optimal SSF conditions were:reaction temperature,35℃;substrate concentration,100 g·L^(-1);initial fermentation liquid pH,5.0;enzyme loading,30 FPU·g21.Under these conditions,the ethanol concentration increased with reaction time,and after 72 h,ethanol was obtained in 65.8%yield with a concentration of 22.7 g·L^(-1).