Optimization of Freeze-drying Protective Agents for Lactobacillus plantarum KLDS1.0391 by Response Surface Methodology

In this study, the Single Factor Test（SFT） was used to optimize the pre-freezing conditions of L. plantarum KLDS1.0391（KLDS1.0391）. Further, the Freeze-Drying Protective Agents（FDPA） of KLDS1.0391 was optimized by Response Surface Methodology（RSM）. The optimum pretreatment conditions were as the follows： initial concentration of KLDS1.0391 was 1011 CFU · m L-1 and KLDS1.0391 was pre-freezed at –80℃ for 8 h to achieve the survival rate of 46.21%. The main components of FDPA were skim milk, sucrose, sodium glutamate and Tween-80. And the influence of four factors on the survival rate of KLDS1.0391 in freeze-drying was in order as the follows： skim milk〉sucrose〉Tween-80〉sodium glutamate. The optimal FDPA composition was skim milk 11.3%, sucrose 9.8%, sodium glutamate 5.1% and Tween-80 0.2%. Under the above conditions, the survival rate of the cells was 82.98%. Comparing the predicted values, the relative error was 0.37% and the difference was not significant, which indicated that the established model could effectively reflect the actual protection of FDPA to KLDS1.0391.

Effects of a Dehydrating Agent on Dry Matter Accumulation and Nutritional Quality of Different Maize Varieties

The high water content of corn grain at harvest is a challenge in Northeast China,where the growing season is short.Using a dehydrating agent before harvest can help corn seeds dehydrate quickly.The dry matter accumulation and nutrient quality of maize were systematically studied by field experiments and instrumental analysis using maize varieties of different maturities as test materials.The results showed that the accumulation of dry matter was enhanced by an increased dosage of a dehydrating agent.When the dehydrating agent dosage reached 1800 mL•hm-2,the dry matter accumulation of early-maturing varieties increased by 24.1 g,and the water content decreased by 8.08%.Different maize varieties were treated with the same dose;early-maturing varieties showed significant effects on grain dry matter accumulation,and kernel dry matter accumulation increased by 7%.The effects of different doses on grain dehydration were obvious,and the effects on different maize varieties varied.Medium-ripening maize varieties showed the most significant effect,with a 19.5%reduction in water content.The effects of dehydrating agent doses on maize yield,grain nutrient quality and seed germination rate were not significant.Therefore,a dehydrating agent promoted the accumulation of dry matter in grain and accelerated the rapid dehydration.

Topical biological agents targeting cytokines for the treatment of dry eye disease

Because inflammation plays a key role in the pathogenesis of dry eye disease and Sjogren's syndrome, topical anti-inflammatory agents such as corticosteroids and cyclosporine A have been used to treat inflammation of the ocular surface and lacrimal gland. Systemic biological agents that target specific immune molecules or cells such as tumor necrosis factor(TNF)-α, interferone-α, interleukin(IL)-1, IL-6, or B cells have been used in an attempt to treat Sjogren's syndrome. However, the efficacy of systemic biological agents, other than B-cell targeting agents, has not yet been confirmed in Sjogren's syndrome. Several studies have recently evaluated the efficacy of topical administration of biological agents targeting cytokines in the treatment of dry eye disease. Topical blockade of IL-1 by using IL-1 receptor antagonist could ameliorate clinical signs and inflammation of experimental dry eye. Using a mouse model of desiccating stress-induced dry eye, we have demonstrated that topical application of a TNF-α blocking agent, infliximab, could improve tear production and ocular surface irregularity, decrease inflammatory cytokines and Th-1 CD4+ cells on the ocular surface, and increase gobletcell density in the conjunctiva. Although controversy still remains, the use of topical biological agents targeting inflammatory cytokines may be a promising therapy for human dry eye disease.

High energy density in ultra-thick and flexible electrodes enabled by designed conductive agent/binder composite

Thick electrodes can increase incorporation of active electrode materials by diminishing the proportion of inactive constituents,improving the overall energy density of batteries.However,thick electrodes fabricated using the conventional slurry casting approach frequently exhibit an exacerbated accumulation of carbon additives and binders on their surfaces,invariably leading to compromised electrochemical properties.In this study,we introduce a designed conductive agent/binder composite synthesized from carbon nanotube and polytetrafluoroethylene.This agent/binder composite facilitates production of dry-process-prepared ultra-thick electrodes endowed with a three-dimensional and uniformly distributed percolative architecture,ensuring superior electronic conductivity and remarkable mechanical resilience.Using this approach,ultra-thick LiCoO_(2)(LCO) electrodes demonstrated superior cycling performance and rate capabilities,registering an impressive loading capacity of up to 101.4 mg/cm^(2),signifying a 242% increase in battery energy density.In another analytical endeavor,time-of-flight secondary ion mass spectroscopy was used to clarify the distribution of cathode electrolyte interphase(CEI) in cycled LCO electrodes.The results provide unprecedented evidence explaining the intricate correlation between CEI generation and carbon distribution,highlighting the intrinsic advantages of the proposed dry-process approach in fine-tu ning the CEI,with excellent cycling performance in batteries equipped with ultra-thick electrodes.

煤气化气用于气基竖炉生产DRI技术的进展

介绍了煤气化气用于Midrex和HyL技术的发展和工业化应用现状。同时介绍了煤气化气技术的工业化现状及不同工艺的特点,对适用于Midrex和HyL工艺的煤气化技术进行了分析。Midrex与HYL技术都对煤气化气有一定要求,相比来说,HYL要求得更严格一些。Lurgi法制得的煤气化气经过脱CO2后可直接用于Midrex和HYL竖炉;用Texaco、Undok和Shell技术制得的煤气化气都需经过处理和转换才可用于Midrex和HYL竖炉。

Current understanding of grapevine defense mechanisms against the biotrophic fungus (Erysiphe necator), the causal agent of powdery mildew disease

The most economically important disease of cultivated grapevines worldwide is powdery mildew(PM)caused by the ascomycete fungus Erysiphe necator.The majority of grapevine cultivars used for wine,table grape,and dried fruit production are derived from the Eurasian grape species Vitis vinifera because of its superior aroma and flavor characteristics.However,this species has little genetic resistance against E.necator meaning that grape production is highly dependent on the frequent use of fungicides.The integration of effective genetic resistance into cultivated grapevines would lead to significant financial and environmental benefits and represents a major challenge for viticultural industries and researchers worldwide.This review will outline the strategies being used to increase our understanding of the molecular basis of V.vinifera susceptibility to this fungal pathogen.It will summarize our current knowledge of different resistance loci/genes that have evolved in wild grapevine species to restrict PM infection and assess the potential application of these defense genes in the generation of PM-resistant grapevine germplasm.Finally,it addresses future research priorities which will be important in the rapid identification,evaluation,and deployment of new PM resistance genes which are capable of conferring effective and durable resistance in the vineyard.

A reservoir drying method for enhancing recovery of tight gas

Based on the study of damage mechanisms of generalized water blocking and related water-blocking removal methods, the drying agents for enhancing tight gas reservoir recovery were developed, and the basic properties, injection mode and drying effect of the drying agents were evaluated. The chemical effect, thermal effect, salt resistance, salt resistance formulas and delay mechanism of the drying agent systems for different types of tight reservoirs were investigated through lab experiment. The solubility and solubilization properties of supercritical carbon dioxide on drying agent systems were tested.The injection mode of dissolving drying agent in supercritical carbon dioxide was proposed. The mechanisms of supercritical carbon dioxide with water in micropores of formation matrix were analyzed. Micro-pore structures and seepage characteristics of reservoir before and after drying were compared. Based on the characterization in combination of NMR and laser etched pore structure model, drying effects of the drying agents on bound water of different occurrences were evaluated qualitatively and quantitatively. Lattice Boltzmann method was used to evaluate the influence of drying effect on gas micro-seepage ability.The influence of drying effect on productivity and production performance of gas well was analyzed by numerical simulation.The drying effect can greatly reduce water saturation of tight reservoir and improve the gas seepage capacity in near wellbore and fractures. This work can provide guidance for developing new measures in enhancing recovery of tight gas reservoirs.

Preparation of Cationic Starch by Electromagnetic Dry Process (EMDP)

Introduction Cationic starches are a series of products of which various sorts with different properties and usages can all be produced via cationic reactions by using different types of etherification agents under different conditions. As an additive and strengthening agent,

基于冻干草莓花青素稳定性的复合涂膜护色剂研究

文章研究了冻干草莓在贮藏过程中色泽的变化。将草莓原料用不同配比的柠檬酸、异抗坏血酸钠和海藻糖复合涂膜处理,然后将其冻干,比较不同贮藏环境下冻干草莓中花青素的稳定性。研究表明1.0%柠檬酸、1.5%异抗坏血酸钠和1.0%海藻糖组成的复合涂膜护色剂对草莓中花青素含量的保留效果较好。最佳涂膜护色剂在光照室温25℃条件下贮藏90 d的草莓中花青素损失率为48.9%;对照组花青素损失率为60%。与对照组相比,处理后的冻干草莓在贮藏过程中外观和品质都较好。

不同载体剂对冻干生姜粉末品质的影响

为探究麦芽糊精、海藻糖、阿拉伯胶对冻干生姜粉品质的影响,对添加载体剂后冷冻干燥的生姜粉的得率、物理特性、活性成分、粒径进行测定,用差示扫描量热法分析生姜粉在升温过程中的热流变化,并用傅里叶红外光谱法对特征基团进行分析,结果显示:与直接冻干的生姜粉相比,添加载体剂制备的样品的得率、物理特性及活性成分含量均有所提高,阿拉伯胶组得率最高;麦芽糊精组色差、吸湿性最小,生姜蛋白酶活力最高(65.84 U/g),姜辣素含量最高(24.4 mg/g);海藻糖组溶解度最高。DSC曲线显示:添加载体剂的生姜粉玻璃态转化温度均有所提高,其中阿拉伯胶组最高,性质更稳定。通过红外光谱分析,3种生姜粉的主要基团无明显变化。综合考虑,麦芽糊精是冷冻干燥生姜粉生产中保留生化活性和保持功能特性的最佳载体剂。

水分活度降低剂对半干武昌鱼品质的影响

以半干武昌鱼为研究对象,通过测定水分活度(water activity,a_(w))、水分状态、菌落总数(total viable counts,TVC)、酵母菌总数、总挥发性盐基氮(total volatile basic nitrogen,TVB-N)含量、硫代巴比妥酸反应物(thiobarbituric acid reactive substances,TBARS)值及感官评分,研究不同a_(w)降低剂对半干武昌鱼水分状态及品质的影响。结果表明:a_(w)降低剂种类和添加量对半干武昌鱼的a_(w)、水分状态及理化指标有显著影响,且添加量的影响大于种类;海藻糖、山梨糖醇和丙三醇对半干武昌鱼的a_(w)均有一定的降低作用,丙三醇对a_(w)的降低效果最好,添加6%丙三醇时,可将半干武昌鱼的a_(w)从0.917降低至0.873;随着海藻糖、山梨糖醇和丙三醇添加量的增加,半干武昌鱼肉的T_(22)显著减小(P<0.05),T_(23)无显著差异(P>0.05),其不易流动水比例显著增加(P<0.05),而自由水比例显著降低(P<0.05);相对于对照组,随着a_(w)降低剂添加量的增加,半干武昌鱼的TVC、酵母菌总数、TVB-N含量、TBARS值均显著降低(P<0.05),其中6%丙三醇组的各项指标最优。a_(w)降低剂的添加可有效降低水分自由度和流动性,减缓半干武昌鱼品质劣变。

无氟防水剂X-702M在化纤面料上的洗后晾干应用

研究了一款无氟聚氨酯防水剂X-702M在化纤面料上的洗后晾干防水性能。织物经过X-702M处理后的手抓痕较浅,且具有较柔软的手感。探讨了不同交联剂对化纤面料洗后晾干防水性能的影响。结果发现,交联剂AX-101Z洗后晾干的防水性能较好。当X-702M用量为50 g/L、AX-101Z用量为10 g/L时,织物具有较好的防水性能、洗后晾干防水性能、手抓痕、手感,在化纤面料上可以做到初期防水性能为5级(100分),洗涤5次后室温晾干防水性能达到3~4级(80~90分)。

水分活度降低剂在虾干加工中的应用研究

在单因素试验的基础上,采用L9(34)正交优化试验,研究了不同水分活度降低剂在虾干加工中的应用。结果表明:单因素试验表明,水分活度降低剂都不同程度地降低对虾干的Aw值,其能力大小为复合磷酸盐>柠檬酸>丙三醇>1,2-丙二醇>乙醇。优化试验表明,复合水分活度降低剂比单一水分活度降低剂降低Aw的能力强,主次顺序为复合磷酸盐>1,2-丙二醇>丙三醇>乙醇;最佳组合为复合磷酸盐0.2%、1,2-丙二醇0.5%、丙三醇1.0%、乙醇1.0%,此时Aw值为0.759。保藏试验表明,Aw值在0.833以下时,保质期可达90d以上。此外添加低剂量水分活度降低剂对虾干色泽、质地、组织结构和风味基本无影响。

菊花保色技术研究

以黄色菊花为材料,制定了7种保色剂,通过不同的处理方法,筛选出适宜的保色方法。结果表明,B剂、C剂、E剂、F剂对菊花立体干花的保色效果均较好,D剂和G剂对花瓣具有一定的软化效果,但保色效果差;保色剂吸水加浸泡处理的保色效果最佳;不同花瓣层次处理中,以中层花瓣的保色效果最佳,其次是外层花瓣,内层花瓣的保色效果最差。可见,以B剂、C剂、E剂、F剂吸水加浸泡处理黄菊均能达到较好的保色效果,其中层花瓣适宜用来制作压花艺术品。

平凉钙基膨润土干法钠化工艺研究

采用干法工艺,对甘肃平凉膨润土进行钠化改性,分别从不同钠化剂(碳酸钠、氯化钠、氢氧化钠)的选择和配比、钠化高混时间、自然放置时间等因素对钠化土性能的影响进行了研究。用FTIR和XRD对钠化土进行分析,结果表明,钠化土在不改变原土结构的同时发生了阳离子交换,层间距明显增大。

屎肠球菌QW256冻干保护剂优化及菌粉贮藏稳定性研究

试验旨在探究屎肠球菌QW256菌粉制备工艺。研究屎肠球菌QW256菌粉制备过程中的离心条件、保护剂与复配、菌粉贮藏稳定性等因素对菌体存活率的影响。结果显示:菌体收集的最佳离心条件为6000 g、10 min,悬浮基质为1.9%硫代硫酸钠溶液,优化后的最佳冻干保护剂配方为甘露醇25.38 g/L、蔗糖34.65 g/L、甘氨酸4.17 g/L和抗坏血酸钠1.57 g/L;在该条件下,屎肠球菌冻干存活率达95%以上,菌粉在25℃保藏100 d的存活率达85%以上。研究表明,复合冻干保护剂的研发对屎肠球菌的冻干及贮藏稳定性具有良好的保护作用。

响应面优化酸浆豆腐直投式高效发酵剂配方

将酸浆乳酸菌与商业菌复合,以复合菌粉的冻干存活率为指标,通过优化复合菌粉保护剂配方制备直投式高效发酵剂。结果表明:以菌泥体积100 mL为基准,复合菌粉保护剂最优配方为酵母粉10 g、麦芽糖11.5 g、海藻糖5 g,此时复合菌粉存活率为83.07%;发酵后期直投式高效发酵剂的发酵能力优于菌液,且储存期间发酵性能不变;由二者制备的酸浆豆腐质构特性没有明显差异,说明直投式高效发酵剂可以代替菌液制作酸浆豆腐。

水性自干腻子的研制

探讨了水性自干腻子乳液合成的配方工艺，研究了各主要原材料对其性能的影响。

复合嫩化剂对鹅肉干的影响研究

实验探讨了复合嫩化剂对鹅肉干品质的影响。以氯化钙、木瓜蛋白酶、复合磷酸盐(焦磷酸钠、亚硝酸钠、异抗坏血酸钠)为复合嫩化剂,通过感官评分及剪切力的综合指标,确定复合嫩化剂的配方为氯化钙含量1.0%、木瓜蛋白酶含量0.4%、复合磷酸盐含量为0.2%。

“一步法”生产直接还原铁配煤试验研究

采用"一步法"工艺进行了直接还原铁配煤试验研究,在保证提高还原铁产品质量的前提下,通过改良还原剂配方来提高福建本地无烟煤的应用比例以降低还原剂成本。试验结果表明,福建本地无烟煤与省外优质煤按照一定比例混合,得到的直接还原铁产品TFe品位可达到90.73%、金属化率95.44%。本地煤与优质煤混合使用能够充分利用福建丰富的煤矿资源,大大降低优质煤的用量,提高资源利用率,降低生产成本。