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With the combination of surfactant and freeze-drying, we have developed two kinds of graphene spongy structures. On the one hand, using foams of soap bubbles as templates, three-dimensional porous graphene sponges with rich hierarchical pores have been synthesized. Pores of the material contain three levels of length scales, including millimeter, micrometer and nanometer. The structure can be tuned by changing the freezing media, adjusting the stirring rate or adding functional additives. On the other hand, by direct freeze-drying of a graphene oxide/surfactant suspension, a porous framework with directionally aligned pores is prepared. The surfactant gives a better dispersion of graphene oxide sheets, resulting in a high specific surface area. Both of the obtained materials exhibit excellent absorption capacity and good compression performance, providing a broad range of possible applications, such as absorbents, storage media, and carriers.

Reactive nitrogen (N r ) emission from soils, e.g., nitrous acid (HONO) and nitric oxide (NO), is a key process of the global nitrogen (N) cycle and has significant implications for atmospheric chemistry. To understand the underlying mechanisms of soil N r emissions, air-dried or oven-dried soils are commonly used in the laboratory. To date, few studies have compared the effects of different drying methods on soil N r gas fluxes and N fractions. Here, the authors studied soil water content, pH, (in)organic N content, and N r gas fluxes of air-dried, freeze-dried, oven-dried, and fresh soils from different land-use types. The results showed that the soil pH of air-dried and oven-dried samples was significantly lower compared with fresh soil from farmland and grassland, but higher compared with forest soil. The difference in soil pH between freeze-dried and fresh soil (mean ± standard deviation: 0.52 ± 0.31) was the lowest. In general, all drying methods increased the soil NH 4 + -N, NO 3 − -N, and dissolved organic N contents compared with fresh soil (P < 0.05). The maximum HONO and NO flux and total emissions during a full wetting-drying cycle of fresh soil were also increased by air-drying and oven-drying (P < 0.001), but comparable with freeze-dried soil (P > 0.2). In conclusion, all drying methods should be considered for use in studies on the land-atmosphere interface and biogeochemical N cycling, whereas the freeze-drying method might be better for studies involving the measurement of soil N r gas fluxes.

Novel preservation condition without ultra-low temperature is needed for the study of pathogen in marine fishes. Freeze-drying is such a method usually used for preservation of terrigenous bacteria. However, studies using freeze-drying method to preserving marine microorganisms remain very limited. In this study, we optimized the composition of protectants during the freeze-drying of Edwardsiella tarda, a fish pathogen that causes systemic infection in marine fishes. We found that the optimal composition of protectant mixture contained trehalose（8.0%）, skim milk（12.0%）, sodium citrate（2.0%）, serum（12.0%） and PVP（2.0%）. Orthogonal and interaction analyses demonstrated the interaction between serum and skim milk or sodium citrate. The highest survival rate of E. tarda was observed when the concentration of Na Cl was 10.0, 30.0 and between 5.0 and 10.0 g L^-1 for preparing TSB medium, E. tarda suspension and protectant mixture, respectively. When E. tarda was frozen at-80℃ or-40℃ for 6 h, its survival rate was higher than that under other tested conditions. Under the optimized conditions, when the protectant mixture was used during freeze-drying process, the survival rate（79.63%–82.30%） of E. tarda was significantly higher than that obtained using single protectant. Scanning electron microscopy（SEM） image indicated that E. tarda was embedded in thick matrix with detectable aggregation. In sum, the protectant mixture may be used as a novel cryoprotective additive for E. tarda.

Jerusalem artichoke is an economic crop widely planted in saline-alkaline soil. The use of Jerusalem artichoke is of great significance. In this study, the response surface method was employed to optimize the effects of processing variables (extraction temperature, pH, extraction time, and liquid-to-solid ratio) on the yield of Jerusalem artichoke pectin. Under the optimal extraction conditions: pH 1.52, 63.62 min, 100°C and a liquid-to-solid ratio of 44.4 mL/g, the maximum pectin yield was predicted to be 18.76%. Experiments were conducted under these optimal conditions and a pectin yield of 18.52±0.90% was obtained, which validated the model prediction. The effects of diff erent drying methods (freeze drying, spray drying and vacuum drying) on the properties of Jerusalem artichoke pectin were evaluated and they were compared with apple pectin. FTIR spectral analysis showed no major structural diff erences in Jerusalem artichoke pectin samples produced by various drying treatments. The antioxidant activities of pectin dried by diff erent methods were investigated using in vitro hydroxyl and DPPH radical scavenging systems. The results revealed that the activities of spray dried pectin (SDP) and apple pectin (AP) were stronger than those of vacuum oven dried pectin (ODP) and vacuum freeze dried pectin (FDP). Therefore compared with the other two drying methods, the spray drying method was the best.

Poly（Imino Ketone） （PIK） is a group of novel high performance polymer material with excellent thermal properties and dissolubility. Aiming at the requirements of inertial confined fusion （ICF） studies on low density polymer foams, we firstly synthesized poly（imino imino ketone） （PIIK） by palladium catalyzed C-N cross-coupling reaction, and successfully prepared the PIIK foam material with a density of 80-300 mg/cm3 by using PIIK as the raw material with thermal-induced phase separation and lyophilization technique. Mercury injection method was used to determine the structure of PIIK foams, and the results indicated that the mean pore diameter was lower than 5 ~tm and it had relatively high voidage and specific surface area.

Chemical modification/ambient drying method and freeze drying method were introduced to research the synthesis of mesoporous silica aerogels. By analyzing N2 gas adsorption/desorption isotherms, the fractal geometric characteristics of gels were focused. The overall surface fractal dimensions were determined by analyzing N2 gas adsorption branch and a Frenkel-Halsey-Hill （FHH） equation was empolyed to determine surface fractal dimension Df It is found that, during ambient drying process, VTMCS/VWetgel ratio plays a crucial role in the changes of geometric feature, the key point is 50%, when the ratio is lower, and surface roughness increases with the ratio, when it exceeds 50%, the surface is almost unaffected by the modification. While freeze drying always tends to get larger Df freeze drying process could cause a rough surface of the gels. Compared with traditional porosity and specific surface area analyses, fractal geometry may be expected to be favorable for mesoporous structural analyses of materials.

The paper was to study the inhibitory effect of recombinant freeze-drying chicken interferon against Newcastle disease virus （NDV） F48E10. Nine-day-old chicken embryos were inoculated with recombinant freeze-drying chicken interferon via allaotoic sack, while 10-day-old chicken embryos were inoculated with NDV F48E10, and in vivo protective efficacy of interferon on chichen embryos was studied. The results showed that the recombinant freeze-drying chicken interferon at the dose of 1.28 mg/embryo reached the protection ratio of 90% on chicken embryo infected by F48E10.

Long-term preservation and easy transportation of human bone marrow-derived mesenchymal stem cells （hBM-MSCs） will facilitate their application in medical treatment and bioengineering. A pilot study on the freeze-drying of hBM-MSCs was carried out. hBM-MSCs were loaded with trehalose. The glass transition temperature of the freeze-drying suspension was measured to provide information for the cooling and primary drying experiment. After freeze-drying, various rehydration processes were tested. The highest recovery rate of hBM-MSCs was （69.33±13.08）%. Possible methods to improve freeze-drying outcomes are discussed. In conclusion, the present study has laid a foundation for the freeze-drying hBM-MSCs.

With the vacuum freeze-drying technology, frozen dumpling wrappers were prepared, to investigate the effects of six kinds of food additives, including modified starch, compound phosphate, maltodextrin, guar gum, distilled monoglycerides and transglutaminase （TG enzyme）, on the drying rate, rehydration ratio and sense value of the frozen dumpling wrappers. The results showed that, with respective addition of 6% modified starch, O. 1% compound phosphate, 10% maltodextrin, 0.4% guar gum, 0.4% distilled monoglyceride and 0.3% transglutaminase, the drying rate, rehydration ratio and sense value of the frozen dumpling wrappers were the highest.

Chitosan—L-lactic acid composite scaffold for the regeneration of peripheral nerve is obtained by grafting L-lactic acid onto the amino groups in chitosan with combined vacuum freezer drier. The composite scaffold was characterized by ATR-FTIR and SEM. The scaffold has a better graft efficiency and has a dense inner layer and a loose outer layer with porous structure, and the pore size is about 100 μm.The NGF release properties of the scaffold were investigated. The experimental results showed that, at the 1st day, 15.2 ng of NGF on average was released from the scaffold. From day 2 to day 10, the release rate obviously slowed down and 1.64 ng of NGF was released on average every day. After 10 days, the release rate was slower and 10.3 ng of NGF was released on average every day. After 60 days, NGF could also maintained a certain concentration. These properties show that the scaffold is a better carrier for NGF which can be more advantageous to the regeneration of the damaged peripheral nerve. As a result, this composite scaffold would be an ideal candidate for the regeneration of damaged peripheral nerve.