Tuning combined steam and dry reforming of methane for “metgas”production: A thermodynamic approach and state-of-the-art catalysts

Nowadays,combined steam and dry reforming of methane(CSDRM)is viewed as a new alternative for the production of high-quality syngas(termed as"metgas",H2:CO of 2.0)suitable for subsequent synthesis of methanol,considered as a promising renewable energy vector to substitute fossil fuel resources.Adequate operation conditions(molar feed composition,temperature and pressure)are required for the sole production of"metgas"while achieving high CH4,CO2 and H2O conversion levels.In this work,thermodynamic equilibrium analysis of CSDRM has been performed using Gibbs free energy minimization where;(i)the effect of temperature(range:200-1000℃),(ii)feed composition(stoichiometric ratio as compared to a feed under excess steam or excess carbon dioxide),(iii)pressure(range:1-20 bar)and,(iv)the presence of a gaseous diluent on coke yields,reactivity levels and selectivity towards"metgas"were investigated.Running CSDRM at a temperature of at least 800℃,a pressure of 1 bar and under a feed composition where CO2-H2O/CH4 is around 1.0,are optimum conditions for the theoretical production of"metgas"while minimizing C(S)formation for longer experimental catalytic runs.A second part of this work presents a review of the recent progresses in the design of(principally)Ni-based catalysts along with some mechanistic and kinetic modeling aspects for the targeted CSDRM reaction.As compared to noble metals,their high availability,low cost and good intrinsic activity levels are main reasons for increasing research dedications in understanding deactivation potentials and providing amelioration strategies for further development.Deactivation causes and main orientations towards designing deactivationresistant supported Ni nanoparticles are clearly addressed and analyzed.Reported procedures based on salient catalytic features(i.e.,acidity/basicity character,redox properties,oxygen mobility,metal-support interaction)and recently employed innovative tactics(such as confinement within mesoporous systems,stabilization through core shell structures or on carbide surfaces)are highlighted and their impact on Ni0reactivity and stability are discussed.The final aspect of this review encloses the major directions and trends for improving synthesis/preparation designs of Ni-based catalysts for the sake of upgrading their usage into industrially oriented combined reforming operations.

A combined treatment for patients with dry eye and associated laryngopharyngeal reflux:a real-life approach

AIM:To evaluate the efficacy and tolerability of administering a combined therapy in patients with dry eye syndrome(DES)and associated laryngopharyngeal reflux(LPR).METHODS:The study was retrospective,open,observational,and conducted in a real-life setting.Patients had pathological symptom assessment in dry eye(SANDE)and reflux symptom index(RSI)at baseline.Patients were re-assessed after 1mo and at the end of treatment.The treatment consisted of a three-month course based on the combined therapy:Gastroftal eye drops,one drop three times a day,and Gastroftal tablets,two tablets after lunch and two tablets after dinner.Tear break-up-time(TBUT)test,Schirmer test,RSI,and SANDE questionnaire were evaluated.RESULTS:The study included 253 patients.The mean age was 58±11.19y.TBUT test score and Schirmer’s test significantly increased(both P<0.001)after 1mo and at the end of treatment.The RSI score and SANDE scores significantly decreased(both P<0.001)after 1mo and at the end of treatment.CONCLUSION:The current,retrospective,and open study shows that combined therapy using Gastroftal eye drops and tablets could represent a valuable option in managing patients with DES associated with LPR.

Experimental Investigation on Flow and Drying Characteristics of Impinging Stream Drying

Based on the experimental investigation of one-stage semi-circular impinging stream drying, the experiments with the two-stage semi-circular, as well as the vertical and semi-circular combined impinging stream drying were conducted. The variations of system pressure drop, the mean residence time of particles with the mass flow-rate ratio and air velocity etc, were determined. The influences of inlet air temperature, mass flow-rate ratio, initial moisture content of particles and air velocity etc. on drying characteristics were also studied. The results indicate that the vertical and semi-circular combined impinging stream drying can make full use of the advantages of both the vertical and semi-circular impinging stream drying. Reasonable mass flow-rate ratio, air velocity, and higher inlet air temperature should be used for less energy consumption and cost during drying process.

热风-真空冷冻联合干燥对脆性龙眼果干品质及益生活性的影响

[目的]研究热风-真空冷冻联合干燥对脆性龙眼果干品质及益生活性的影响,为高品质龙眼果干工业化节能干燥模式提供理论依据.[方法]以热风干燥、真空冷冻干燥龙眼果干为对照,比较分析热风-真空冷冻联合干燥对脆性龙眼果干水分含量、水分活度、皱缩率、复水比等理化特性和总糖、多糖等营养品质的影响.同时采用GC-MS测定风味物质变化,电量表测定能源消耗量.并选用植物乳杆菌和嗜酸乳杆菌发酵龙眼果干,比较发酵过程中活菌数、总糖、还原糖以及短链脂肪酸的变化,评价热风-真空冷冻联合干燥对龙眼体外益生活性的影响.[结果]热风-真空冷冻联合干燥龙眼果干的水分含量、水分活度和皱缩率显著低于热风干燥,而复水比显著高于热风干燥.在总糖、多糖含量以及挥发性风味物质种类和总量上,热风-真空冷冻联合干燥低于真空冷冻干燥而高于热风干燥.在能源消耗上,热风-真空冷冻联合干燥比真空冷冻干燥节约干燥时间12.16%,节约单位能耗25.40%.在益生活性方面,植物乳杆菌和嗜酸乳杆菌均能通过发酵龙眼干增加活菌数量,利用龙眼干中的总糖产生短链脂肪酸,降低发酵液pH,且益生效果受干燥方式和菌株种类的影响较大.当植物乳杆菌发酵热风-真空冷冻干燥的龙眼果干48 h后,活菌数生长最多可达12.40 lg cfu/mL,高于真空冷冻干燥、热风干燥和新鲜龙眼.嗜酸乳杆菌发酵48 h后,热风-真空冷冻联合干燥活菌数达11.84 lg cfu/mL,与真空冷冻干燥接近,低于热风干燥,但高于新鲜龙眼.[结论]热风-真空冷冻联合干燥结合了热风干燥和真空冷冻干燥两种干燥方式的特点,可以显著缩短干燥时间,节约能耗,提高干燥效率和果干品质.

热风远红外联合干燥肉脯的工艺优化及其品质研究

为提高肉脯品质,本文研究了不同干燥技术对肉脯品质的影响,以水分含量、剪切力、色差和质构为指标,通过单因素和正交试验优化热风-远红外联合干燥肉脯的工艺条件,确定干燥模型,并对比分析微波、热风、远红外干燥技术对肉脯品质的影响。结果表明:热风-远红外联合干燥肉脯的最佳工艺为:第一段热风干燥温度Ⅰ170℃,第二段热风干燥温度Ⅱ250℃,第三段红外烤制温度Ⅲ260℃,干燥100 s,制得肉脯的水分含量低(13.54±0.48) g/100 g,嫩度高,易咀嚼,符合Modified Henderson and Pabis干燥模型(R2=0.9976);与微波干燥、热风干燥和远红外干燥相比,热风-远红外联合干燥的肉脯品质最佳,改善了产品的感官质量,水分含量、剪切力、硬度、咀嚼性、L*值和a*值分别是热风干燥的92%、55%、60%、46%、109%和121%,胶粘性和b*值无显著差异。该研究为肉脯的干燥加工提供了理论依据。

冻干骨松质与转染有血管内皮细胞生长因子的骨髓基质干细胞体内成骨实验

目的:探讨冻干骨松质与转染有血管内皮细胞生长因子(VEGF)的骨髓基质干细胞(BMSC)能否在体内更有效地成骨。方法:采用新西兰大白兔BMSC体外培养扩增,然后用脂质体的方法将VEGF转染入该BMSC,再使其附着于同种异体冻干骨松质,并植入自体肌袋。8周后取标本进行苏木精-伊红染色、三色法染色观察。结果:8周时可见到转染有VEGF的BMSC复合冻干骨松质组在标本的表面有软骨和骨质形成,BMSC复合冻干骨松质组在标本的表面有成骨细胞、破骨细胞出现,并有类骨质形成,而单纯植入冻干骨松质组仅有大量纤维包裹。结论:转染有VEGF的BMSC复合冻干骨松质具有较好成骨活性,优于单纯BMSC复合冻干骨松质。

罗汉果后熟指标与适宜烘烤“温度—时间”组合探讨

【目的】明确罗汉果原料鲜果后熟指标,建立烘烤＂温度—时间＂组合,为提升罗汉果干果品质提供技术支持。【方法】以罗汉果品种青皮果为试验材料,通过研究后熟温度和后熟时间对原料鲜果后熟变化的影响,明确罗汉果鲜果完成后熟的技术指标;设定7个烘烤温度,记录原料鲜果在相应温度下烘烤至水含量≤15%达标时所耗时间,建立烘烤＂温度—时间＂组合,探讨不同组合对黄熟罗汉果鲜果烘烤效果的影响,确定最佳烘烤组合。【结果】采后青皮果在昼温/夜温为（31±2）℃/（27±2）℃的条件下后熟11 d,黄熟果率〉90%,后熟13 d的鲜果失水率达36.4%;不同后熟时间的原料鲜果烘烤耗时不同,后熟3-5 d的非黄熟果与后熟13 d的黄熟果在同一温度下烘烤至果实水含量≤15%,耗时差异达显著水平（P〈0.05）,最长相差8.0 d;以黄熟鲜果为烘烤原料,在建立的7个烘烤＂温度—时间＂组合条件下进行烘烤,以组合（60±1）℃-6.0 d的烘烤效果最佳,干果果壳黄色率100%,果囊膨化充分、香气浓郁、无焦糊,总甜苷含量较其他组合提高了4.1%以上,且干果品质较传统干果有明显提升,口感清香甜爽。【结论】以＂黄熟＂（罗汉果鲜果壳变为黄色）作为罗汉果鲜果后熟完成的技术指标,表达直观、简单,可操作性强;以＂温度—时间＂组合为单元,设置全自动烘烤程序,能更好地保证罗汉果干果品质,且以（60±1）℃-6.0 d的干果品质最佳。

我国制茶工艺技术的发展与方向

本文概述了我国制茶工艺技术的发展与方向:在乌龙茶(青茶)加工工艺中引入"台式"乌龙茶轻萎凋、轻摇青等做法,创造出偏绿型的清香型乌龙茶;在工夫红茶加工干燥工艺中,引入做形辅助成形工艺;在普洱茶加工中引入黑茶人工后发酵工艺,创制出熟普;乌龙茶做青工艺渗透到绿茶与红茶的加工中;将多种加工工艺有效结合,改善目标茶香气、滋味等感官品质。制茶工艺技术发展成效卓著,丰富了茶叶产品类型,提升了产品质量。

不同给药方法治疗急性心力衰竭大鼠的疗效对比研究

目的:探讨治疗急性心力衰竭大鼠的最佳给药方法。方法:选取健康雄性大鼠80只,以随机数字表法分为空白对照组、模型组、附子一号组、干姜一号组、姜附一号组、附子二号组、干姜二号组、姜附二号组等8组,每组各10只。附子一号组、干姜一号组、姜附一号组大鼠按20 ml/kg灌胃给予相应药液,模型组大鼠灌胃给予同体积纯水,1日1次,连续7 d;附子二号组、干姜二号组和姜附二号组于造模成功后一次性给予药物。于一号组末次给药后,观察不同给药方法对急性心力衰竭大鼠血流动力学参数、心肌组织以及B淋巴细胞瘤-2基因(Bcl-2)、Bcl-2相关X蛋白(Bax)和动力相关蛋白1(Drp1)的影响。结果:血流动力学结果显示,姜附的缓解作用显著大于单用附子,同时,一号组大鼠各指标改善率普遍高于二号组;心肌组织病理学显示,姜附改善大鼠心肌组织损伤的病理变化作用优于附子,此外,附子、姜附一号组大鼠个指标缓解率显著优于二号组;Bax、Bcl-2以及Drp1的核酸水平显示,附子、干姜以及姜附一号组大鼠各指标缓解率均大于二号组,且姜附组优于附子及干姜单独给药组。结论:对于急性心力衰竭大鼠模型而言,预防性给药的效果优于一次性给药,提示相关实验可采纳预防与治疗结合的给药方法。

干制加工型白萝卜雄性不育系及组合农艺性状分析

为筛选出高产、优质的干制加工型白萝卜优良不育系及组合,本研究运用顶交法对前期转育获得的10个不育系和1个优良自交系进行杂交组配,对10个测配组合的株高、株幅、叶长、叶宽、根长、根粗、单根重、糠心8个农艺性状进行一般配合力、相关性分析、通径分析及主成分分析。结果表明,‘237A’、‘237B’、‘231A’不育系的根长和单根重性状表现优异,具有配制优良干制加工型萝卜新品种的应用潜力;株高、根长、单根重与糠心呈正相关,肉质根根长与单根重的直接通径系数为P=1.029,株高对单根重呈负效应,直接通径系数P=-0.1937。但株高通过根长、叶长、株幅的间接作用达到了较大的正向效应(0.9959)。综上,结合主成分分析结果,最终确定‘231A’ב青首’‘、237B’ב青首’‘、19072’ב青首’为加工型白萝卜优质组合,可用于生产试验。同时建议在育种工作中把根长、株高、叶长、株幅和糠心作为加工型白萝卜高产优质的主要农艺性状来进行考量。

前处理方式对冻干鸡肉制备及其特性的影响

为了改善冻干鸡肉的生产效率及特性,利用超声波、菠萝蛋白酶、菠萝蛋白酶-超声波联合进行前处理,探究其对冻干鸡肉的影响。结果表明,经超声波、联合处理样品的干燥速率高于未处理组,联合处理样品的总失水率显著高于其他组(P<0.05);联合处理样品的肌原纤维蛋白(myofibrillar protein,MP)溶解度以及电位绝对值显著高于其他组(P<0.05),其硬度、复水后嫩度、肌原纤维小片化指数(myofibril fragmentation index,MFI)、MP含量及平均粒径显著低于其他组(P<0.05);扫描电镜显示联合处理样品的肌原纤维断裂更明显;十二烷基硫酸钠-聚丙烯酰胺凝胶电泳(sodium dodecyl sulfate-polyacrylamide gel electrophoresis,SDS-PAGE)显示联合处理能够降解肌球蛋白重链(myosin heavy chain,MHC)、肌动蛋白(actin)和原肌球蛋白(tropomyosin,TM),导致其条带变浅。联合处理有利于冻干鸡肉的制备生产以及感官、理化等特性的改善,能有效提高其品质。

《伤寒论》干姜药对应用探析

对干姜在《伤寒论》中的作用及其配伍应用进行归纳、整理,从中学习仲景辨证用药,以期对临床应用有所裨益。如干姜与温热药配伍主要用于寒证,包括脏腑里虚寒和寒邪内侵,发挥温里作用;干姜与苦寒药物相配,主要用于寒热错杂证,发挥辛开苦降或温清共用之效。

干制辣椒产量及色价杂种优势评估

本试验以52份F_(1)代辣椒作为试验材料,测定其理论总产量、优果产量、果实失水率、色价等主要目标性状,依据试验总平均和方差划分出高产和低产判别区间,并对其进行综合评估,筛选优势杂交组合。结果表明,52份F_(1)在总产量、优果产量、失水率和色价上存在极显著差异。以大于试验总平均值为筛选指标,选出12个优势杂交组合,其中簇×羊类型组合在一级果产量、总产量、失水率和色价方面,筛选出的优势组合率最高;羊×甜和簇×甜的杂交组合也有较高的优势率。

Flexibility of MIP Technology

The flexibility of MIP technology to meet market demand is mainly introduced in this study. Their commercial application and technical principle are analyzed too. The MIP technology with wide feed adaptability can form a good combination with other technologies. The MIP technology has been applied extensively in China. Based on this platform, the CGP, MIP-LTG and MIP-DCR technologies have been developed, which can further improve the flexibility of MIP technology. Based on its novel reaction control technique with a sole sequential two-zone riser, the MIP users can easily switch to different operating modes between producing either more clean gasoline and propylene or diesel through changing the catalysts and varying the operating conditions. That offers MIP users with enough production flexibility and a rational production arrangement to meet the market demand. The MIP-DCR technology with less dry gas and coke yields can provide a more flexible operating mode since the catalysts to oil ratio has become an independent variable.

Clinical Study on Combined Acupuncture and Chinese Medicinal Fumigation for Dry Eye Syndrome

Objective:To observe the clinical effect of combined acupuncture and Chinese medicinal fumigation for dry eye syndrome(DES).Methods:A total of 90 DES cases(180 eyes)were randomized into a treatment group of 44 cases and a control group of 46 cases.Combined acupuncture and Chinese medicinal atomizer fumigation was used in the treatment group,whereas Sodium Hyaluronate eye drops was used in the control group.The subjective symptoms,Schirmer I Test(SIT)and Break-up Time(BUT)of tear film were observed before and after treatment.Results:The total effective rate in the treatment group was 78.4%,versus 12.0%in the control group,showing a statistical difference(P<0.01).After treatment,there were between-group statistical differences in SIT and subjective symptom grades(P<0.05,P<0.01).However,there was no between-group statistical difference in BUT grade(P<0.05).Conclusion:Combined acupuncture and Chinese medicinal atomizer fumigation can help alleviate DES symptoms.

Freeze and microwave vacuum combination drying technique for sea cucumber

To improve the quality and efficiency of sea cucumber drying,an orthogonal experiment of freeze and microwave vacuum combination drying technique was carried out.Factors and levels were FD time of conversion point(8 h,16 h and 24 h),initial microwave power density(1.7 W/g,2.0 W/g and 2.3 W/g)and microwave intermittent ratio(12s-on/18s-off,14s-on/16s-off and 20s-on/10s-off).Results showed that the optimal parameters of FD-MVD were 8 h FD conversion point,1.7 W/g initial microwave power density,12 s-on/18 s-off microwave intermittent ratio,and the maximum rehydration rate of 280.71%,the lowest shrinkage rate of 14.48%,the least drying time of 9.25 h and energy consumption of 77316 kJ could be obtained.

氢化物发生-原子荧光光谱法联合测定海米的砷和汞含量

针对传统分析方法同时测定海米As和Hg含量存在操作繁琐、灵敏度不高等问题,对样品前处理过程中的消解体系和消解温度进行了优化,建立了氢化物发生-原子荧光光谱法联合测定海米中砷(As)和汞(Hg)含量的方法。优化条件下,As和Hg元素的最低定量限分别为0.032和0.074μg/L,回收率均在97%以上,相对标准偏差范围为2.77%~6.25%。该方法灵敏、准确、重现性好,可用于海米As和Hg含量的联合分析。

风干板栗太阳能-热泵联合干燥特性与数学模型研究

为研究风干板栗太阳能-热泵联合干燥特性,以新鲜板栗为原料,探讨干燥温度、干燥风速、装载量对风干板栗干燥速率和干基含水率的影响,在不同干燥温度、干燥风速、装载量条件下分别对新鲜板栗进行干燥,并比较了6种数学模型在风干板栗太阳能-热泵联合干燥的适用性,同时以Fick第二扩散定律为依据,确定风干板栗不同干燥条件下的有效水分扩散系数。结果表明:风干板栗干燥过程由调整阶段和降速干燥阶段控制,主要表现为降速干燥;干燥温度越高、干燥风速越高以及装载量越小,干燥至目标含水率所用时间越短,干燥速率越大;干燥过程中,有效水分扩散系数随干燥温度及干燥风速的升高、装载量的降低呈现增大的趋势,干燥温度从15℃升高到35℃,其有效水分扩散系数由3.00124×10^-10 m^2/s增大到8.42115×10^-10 m^2/s,干燥风速由1.0 m/s升高到5.0 m/s,其有效水分扩散系数由4.54717×10^-10 m^2/s增大到9.13767×10^-10 m^2/s;装载量从0.6 kg升高至5.4 kg,其有效水分扩散系数由1.14753×10-9 m^2/s降至3.20443×10^-10 m^2/s;通过比较决定系数(R2)、残差平方和及卡方(χ^2)得出,Page模型为描述风干板栗太阳能-热泵联合干燥的最优模型,验证发现试验值与模型预测值拟合度较高,Pearson相关系数为0.998,二者显著相关(P<0.05),说明Page模型能够较好地反映风干板栗干燥过程中水分变化规律。

基于不同方法评价坚果与果干复配物的抗氧化能力

为科学评价坚果与果干复配物的健康功效,本实验通过化学提取法、体外消化模型、小鼠模型评价多种坚果与果干复配后的抗氧化能力变化。化学提取法分析结果表明,坚果与果干复配后富含酚类物质、脂肪酸和蛋白等营养物质,且1,1-二苯基-2-三硝基苯肼(1,1-diphenyl-2-picrylhydrazyl,DPPH)自由基清除能力、2,2-联氨-双-3-乙基苯并噻唑啉-6-磺酸(2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid),ABTS)阳离子自由基清除能力和铁离子还原能力(ferric ion reducing antioxidant power,FRAP)比坚果组总体显著提高(P<0.05);体外消化模型分析结果表明,与坚果和果干组相比,胃肠道消化后坚果与果干复配物中酚类物质的含量提高了2.90%~60.38%,两种自由基清除率提高了1.23%~18.60%,且坚果与果干适当配比时(6∶4,m/m)抗氧化协同效果最好;小鼠模型实验分析结果表明坚果与果干复配物在体内消化后提高了小鼠血清和肝脏中过氧化氢酶、超氧化物歧化酶活力及总抗氧化能力,并有效抑制了丙二醛的产生,保护了小鼠肝细胞形态的完整性。综上所述,坚果和果干混合具有协同增效抗氧化作用,并在体内外具有良好的抗氧化能力。

分析联用冻干重组人脑利钠肽、左西孟旦治疗急性心力衰竭的临床效果

目的探讨冻干重组人脑利钠肽、左西孟旦联用对急性心力衰竭的临床治疗价值。方法对照组在常规治疗基础上加用冻干重组人脑利钠肽,研究组在常规治疗基础上加用冻干重组人脑利钠肽、左西孟旦,记录两组急性心力衰竭患者治疗前后心功能指标变化情况及不良反应发生情况。结果两组急性心力衰竭患者治疗前LVESV、LVEF、LVEDV指标评价结果对比P>0.05,研究组治疗后LVESV、LVEDV较之前下降幅度以及LVEF水平上升幅度均显著优于对照组,数据对比(P<0.05);两组急性心力衰竭患者治疗期间药物相关各项不良反应发生情况对比P>0.05。结论:在常规给药基础上,应用左西孟旦、冻干重组人脑利钠肽联合治疗急性心力衰竭效果显著,有利于保障患者预后及生活质量。