Study on Nutrient Carrier of Mulch Based on Hydrogel @SiO2.

Soil conservation is one of the best methods to improve soil fertility and enhance crop growth efficiency. Replacing plastic mulch with biomass is an environmentally friendly strategy. Innovative encapsulated soil granules (ESGs) were developed using PVA/PC film as the wall material and rural soil as the core. The PVA/PC was synthesized using 60% protein polypeptide (PC) from leather waste scrap and 35% poly (vinyl alcohol) (PVA), which was optimized for water absorption expansion and water retention performance. The ESG-10 granulated with 10% PVA/PC exhibited good water absorption, moisture retention, and resistance to water solubility. As an auxiliary material for soil improvement, the amount of ESGs mixed with the topsoil at ratios of 0 g/m2, 200 g/m2, and 400 g/m2 was proportional to the soil insulation and moisture retention. In rapeseed cultivation, the experimental results indicated that the soil mulched with ESG-10 can maintain seedling vitality for a long time under low water content conditions.

Study on the anhydrous condensation of collagen polypeptide and tricyanogen chloride.

The molecular weight of collagen-degrading polypeptides (CDPs) extracted using the alkali method from leather scraps must be expanded to improve its utilization effect. A novel polymer (CPP) was synthesized from tricyanogen chloride (TC) and CDP by mechanical force without water. According to the solution viscosity and content of water-soluble matter, the optimal condensation conditions of the n(TC)/n(CDP) and temperature were obtained and the properties of CPP, such as the molecular weight, thermal properties, and isoelectric point were tested and analyzed. The synthesis of CPP was simulated by the substitution of l-threonine containing hydroxyl and amino groups for the condensation reaction of CDP and TC. The result illustrated that only amino groups were involved in the substitution of chlorine accomplished by the SN2 pathway. Based on this, a probable formation mechanism of CPP was proposed. As an illustration, CPP has good utilization values in the preparation of a corrugated paper jelly instead of gelatin. The preparation of polypeptide water-based adhesive by a mechanochemical method not only has good controllability in the production process but also can save water and energy.

Application of wool keratin: an anti-ultraviolet wall material in spray drying.

Low-molecular-weight keratin (LMWK) obtained from wool was employed as a wall material for the spray drying encapsulation of fish oil. Microcapsules with different LMWK contents were prepared, and their anti-ultraviolet performance and other features were studied. The results showed that LMWK was able to improve the encapsulation efficiency of fish oil because of its good emulsifying properties. When the LMWK content was increased from 0 to 10, 30 and 50%, the shelf life of the microcapsules under ultraviolet irradiation increased from 48 to 96 h, 144 h and 168 h, respectively. The strongest absorption efficiency of LMWK is shown in the UVc band. The chemical structure of LMWK did not change during an ultraviolet accelerating ageing test.

Exploration of collagen cavitation based on peptide electrolysis.

Electrochemical modification of animal skin is a new material preparation method and new direction of research exploration. In this study, under the action of the electric field using NaCl as the supporting electrolyte, the effect of electrolysis on Glycyl-glycine(GlyGl), gelatin(Gel) and Three-dimensional rawhide collagen(3DC) were determined. The amino group of GlyGl is quickly eliminated within the anode region by electrolysis isolated by an anion exchange membrane. Using the same method, it was found that the molecular weight of Gel and the isoelectric point of the Gel decreased, and the viscosity and transparency of the Gel solution obviously changed. The electrolytic dissolution and structural changes of 3DC were further investigated. The results of TOC and TN showed that the organic matter in 3DC was dissolved by electrolysis, and the tissue cavitation was obvious. A new approach for the preparation of collagen-based multi-pore biomaterials by electrochemical method was explored.

Gelatin as green adhesive for the preparation of a multifunctional biobased cryogel derived from bamboo industrial waste.

The effective utilization of bamboo industrial waste to produce value-added products is an important subject. In this paper, a multifunctional biobased cryogel derived from bamboo industrial waste was successfully developed. Bamboo fibres were first extracted from bamboo industrial waste and then dispersed in the gelatin solution to produce bamboo fibres/gelatin cryogels (BFs/G cryogels) by a freeze-drying process. The hydrophobicities of BFs/G cryogels were further improved by modification with methyltrichlorosilane. The prepared BFs/G cryogels possessed low density (23.9-29.5 mg/cm3), high porosity (90.41-95.85%), low thermal conductivity (0.031‒0.047 W/m·K) and excellent sound-insulating performance. The presence of rigid bamboo fibres improved the mechanical performance of the BFs/G cryogel. Furthermore, the BFs/G cryogels exhibited high oil absorption capacities of 23-66 times that of their dry weights. The successful development of this cryogel provides a path for the efficient utilization of bamboo industrial waste as a renewable biomass resource.

Fabrication and characterization of one high-hygroscopicity liquid starch-based mulching materials for facilitating the growth of plant.

One high-performance liquid starch-based mulching materials (LSMM) was successfully fabricated by grafting polyacrylic acid (PAA) onto starch then crosslinking with N,N'-methylene-bisacrylamide (MBA). The effects of the dosage of acrylic acid on the performances of LSMM film had been explored. The LSMM was characterized by FTIR, solid state 13C NMR, XRD and SEM. Their application performances by spraying the LSMM on the soil surface also had been discussed. The PAA grafted onto starch significantly improved the properties of LSMM film (tensile strength 20.89 MPa, elongation at break 59.19 %, water absorbency 68.58 g/g and solubility in water 4.5 %). The PAA broke the hydrogen bonds and reduced the crystallinity of starch molecule, which can form the compact structure in LSSM film. As a result, the LSMM showed excellent relative hygroscopicity, water retention, degradability (weight loss 72.61 %) and the effect of facilitating the growth and germination ratio (84.00 %) of lettuce.

The structure and properties of granular cold-water-soluble starch by a NaOH/urea aqueous solution.

The NaOH/urea treatment of starch results in granular cold-water-soluble starch (GCWSS). The research indicated that the optimized condition for this treatment was aqueous solution of 14% w/v NaOH and 12% w/v urea (all dosages based on starch weight) at ambient temperature (25 °C) for 10 min with stirring. The aqueous solution was then treated a water-extraction and alcohol-precipitation method. The solid sample was dried in an oven at 60 °C. The GCWSS displayed a cold-water solubility of ~90%. The GCWSS had lower amylose content. Fourier transform infrared (FTIR) spectroscopy and X-ray diffraction also indicated that it was an amorphous solid with a V-type pattern (single-helix). The NaOH/urea solution could destroy the inter and intra hydrogen bonding of starch thereby decreasing glass transition temperature, and improve the cold water solubility of native starch.

Stabilization and cyclic utilization of chrome leather shavings.

For the sake of the safe and efficient cyclic utilization of chrome leather shavings (CLS), the temporary stabilization of CLS during the storage and transport processes was optimized. Afterwards, the large-scale stabilized CLS degradation and collagen degradation product (CDP) extraction were completed. In this research, hydroxyapatite (HAP) and calcium hydroxide (Ca(OH)2) were for the first time used as stabilizers in the stabilization of CLS. The results showed that both Ca(OH)2 and HAP displayed resistance to chrome leaching, but HAP provided better stabilization effect than Ca(OH)2. The optimized stabilization conditions giving lower chromium leaching concentration were selected: 2% HAP, temperature 300 °C, reaction time 60 min, and initially added water contents of 50%. The reason for HAP and Ca(OH)2 stabilization was proved by energy dispersive X-ray spectroscopy (EDS). Subsequently, the exploitation value of the stabilized CLS was described by large-scale experiment. The hydrolysis of stabilized CLS could obtain the collagen degradation product (CDP), which had 3.52% of free amino content and a molecular weight of 3.4~30 kDa. The filter residue was treated by 5% sulfuric acid solution extraction and pressure filtration again. The extraction solution and final filter residue were dried separately to obtain chromium-containing organic compounds (COP) and industrial gypsum. The COP, used as a filling for tannery, contains 9.37% Cr2O3 content and 90.6% organic content. The industrial gypsum contains 68.37% CaSO4, 0.13% Cr2O3, and 31.5% residual organic or inorganic compounds, which can be used in building materials. No waste water or solid waste was discharged in this experiment process.

The oxidation of potato starch by Electro-Fenton system in the presence of Fe(II) ions.

An efficient method was developed to prepare oxidized potato starch under the pasting point by Electro-Fenton system, in which a complex of sodium citrate and Fe2+ (SC-Fe2+) was used as catalyst, and H2O2 was used as oxidant. In the preparation process the oxidation degree of starch was controlled by the molar ratios of SC-Fe2+ and hydrogen peroxide. The structures and thermal properties of the prepared oxidized starch were characterized by FT-IR, XRD, SEM, DSC and DTG. The characterization results indicated that the obtained oxidized potato starch owned one grainy molecule structure, and displayed a high viscosity (not less than 63 Pa·s) by comparing to the raw starch. The carbonyl and carboxyl contents of oxidized potato starch achieved 0.81 per 100 AGU and 0.79 per 100 AGU, respectively after the raw starch was oxidized. And the oxidized starch showed good thermal stability, which can dramatically improve the application performance of starch-based biomaterials.

Biodegradable films based on gelatin extracted from chrome leather scrap.

A biodegradable film based on gelatin extracted from chrome leather scrap was studied in this paper. According to the results of a variety of characterization, the extracted gelatin contains 13 kinds of amino acid; the chrome content is 30mg/kg, mineral and salt content are both at low levels and the nitrogen content is 43.84%. Its molecular weight has been measured at about 6.5kDa ∼26.6kDa, and the average particle distribution appears to be 125nm with a narrow distribution. When the extracted gelatin was modified with the ß-cyclodextrin to prepare the biodegradable films, the ß-cyclodextrin and gelatin blends can build up perfect compatibility and film-forming properties. Comparing to the gelatin film without ß-cyclodextrin, the viscosity, biodegradability, thermal stability and physical properties of the ß-cyclodextrin and gelatin blends in the present research were significantly increased, especially when the ratio of ß-cyclodextrin to gelatin was 1:2, the biodegradation rates reached 81%, elongation at break 15.74% and the tensile strength 122.34MPa. The blends show perfect swelling properties and overcome the rapid solubility drawback of extracted gelatin.

On spray drying of oxidized corn starch cross-linked gelatin microcapsules for drug release.

Spray-dried gelatin/oxidized corn starch (G/OCS) microcapsules were produced for drug release application. The prepared microcapsules were characterized through a scanning electron microscope (SEM) picture and thermogravimetric analysis (TGA). The swelling characteristics of the G/OCS microcapsules and release properties of vitamin C were then investigated. The results from structural analysis indicated that the presence of miscibility and compatibility between oxidized corn starch and gelatin, and exhibits high thermal stability up to 326°C. The swelling of G/OCS microcapsules increased with increasing pH and reduced with decreasing ionic strength, attributed to the cross-linking between gelatin and oxidized corn starch, ionization of functional groups. Vitamin C release characteristic revealed controlled release behavior in the first 3h of contact with an aqueous medium. This release behavior was independent of the swelling behavior indicating the potential of the encapsulating matrix to produce controlled release across a spectrum of pH environment.

The Preparation and Applications of One Biodegradable Liquid Film Mulching by Oxidized Corn Starch-Gelatin Composite.

Degraded gelatin (Gel) and oxidized corn starch (OCS) as abundant, recyclable, and biodegradable materials can be applied to agricultural production, which has been investigated in this research. Firstly, the prepared oxidized corn starch-gelatin (OCS-Gel) composite material was characterized through a Fourier transform infrared spectrometer (FT-IR), a scanning electron microscope (SEM) picture, and a thermogravimetric analysis (TGA). The OCS-Gel was then used as a liquid film mulching for agricultural production, and the application performances (hygroscopicity, permeability, water retention, etc.) of the OCS-Gel were measured. Finally, the planting rapeseed experiments were carried out, and the germination and growing state of the rapeseed seeds were observed. The results from the structural analysis indicated that OCS-Gel enriches pore structure and exhibits high thermal stability up to 324.8 °C. In the application experiments, the OCS-Gel showed excellent properties of water-absorbing and water-retention and low permeability. In addition, the germination rate of the rapeseed seed reached 80 %, and the height of rapeseeds obviously increased in pot experiments after adding the liquid film mulching.

[Study on hydrothermal stability of the collagen].

The low hydrothermal stability of the raw collagen restricts its usage. To improve the hydrothermal stability of collagen, two kinds of materials with weak astringency were used by experts. The research proved that the synergistic effect was formed during the process. In this study, by using UV, FT-IR, 13CNMR spectra and elemental analysis on the salicylic acid and metal-salicylic complexes, we could get the structural formula of every compound. And then, the hide powder was treated with the compounds. At last, the treated hide powder was tested by DSC. It could be presumed that the Rigid Matrix formed between the collagen doses can increase the hydrothermal stability of raw collagen, The result indicated that salicylic-chrome with large stable constant was better than others in improving the heat resistance of raw collagen, and the denaturalization temperature of hide powder treated with salicylic-chrome was 146.7 degrees C. Salicylic-aluminum was in the second place, the relevant temperature being 145.7 degrees C.