Effects of Controlled Atmospheres with High_O_2 or High_CO_2 Concentrations on Postharvest Physiology and Storability of "Napoleon" Sweet Cherry

Sweet cherries ( Prunus avium L. cv. Napoleon) were stored in controlled atmospheres (CA) of high O(2) (70% O(2) + 0% CO(2)) or high CO(2) (5% O(2) + 10% CO(2)), in modified atmosphere package (MAP, (13% - 18%) O(2) + (2% -4%) CO(2)) and in air (control) at 1 degreesC to investigate the effects of different O(2) and CO(2) concentrations on physiological properties, quality and storability of the fruits during storage. The results indicated that compared with other treatments, CA with high O(2) concentration decreased fruit decay and ethanol content, but increased the accumulation of malondialdehyde (MDA) and stimulated browning. CA with high CO(2) concentration inhibited polyphenol oxidase (PPO) activity, reduced MDA content, maintained vitamin C content and firmness, decreased fruit decay and browning. Soluble solids contents (SSC) were not significantly affected by different atmosphere treatments. 'Napoleon' fruits stored in 5% O(2) + 10% CO(2) for as long as 80 d were of good quality, but only 40, 20 and 30 d stored in MAP, 70% O(2) + 0% CO(2) and air, re-spectively.

Calculation of H_2O-NH_3-CO_2 Vapor Liquid Equilibria at High Concentration Conditions

A vapor liquid equilibrium model and its related interactive energy parameters based on UNIQUAC model for the H2O-NH3-CO2 system without solid phase at the conditions of temperature from 30℃ to 90℃, pressure from 0.1 MPa to 0.4 MPa, and the maximum NH3 mass fraction up to 0.4 are provided. This model agrees with experimental data well (average relative error < 1%) and is useful for analysis of industrial urea production.

Influence of high concentration Zn^(2+) on floatability of sphalerite in acidic system

The influence of high concentration Zn^(2+) on the floatability of sphalerite in an acidic system was investigated via flotation experiments,zeta potential measurements,contact angle measurements,and X-ray photoelectron spectroscopy.The results indicated that Zn^(2+) was adsorbed on the sphalerite surface and a Zn-hydroxyl complex was formed at a pH of 4 and a Zn^(2+) concentration of 4×10^(-2) mol/L.The zeta potential increased and the contact angle decreased from 84.80°to 36.48°,strongly inhibiting the floatability of sphalerite.When S^(2−) or Cu^(2+) activator was used alone,sphalerite was not activated after Zn^(2+) was adsorbed,and its contact angle did not change significantly.However,by using a combination of S^(2−) and Cu^(2+) activators,its floatability was realized after Zn^(2+) adsorption.This result was attributed to the removal of the Zn-hydroxyl complex on the surface of sphalerite by S^(2-).After this removal,Cu^(2+) was adsorbed on the sphalerite surface to form a Cu_(2)S·S^(0) hydrophobic film.

Stomatal response of Pinus sylvestriformis to elevated CO2 concentrations during the four years of exposure

Four-year-old Pinus sylvestriformis were exposed for four growing seasons in open top chambers to ambient CO2 concentration (approx. 350 μmol·mol-1) and high CO2 concentrations (500 and 700 μmol·mol-1) at Research Station of Changbai Mountain Forest Ecosystems, Chinese Academy of Sciences at Antu Town, Jilin Province, China (42oN, 128oE). Stomatal response to elevated CO2 concentrations was examined by stomatal conductance (gs), ratio of intercellular to ambient CO2 concentration (ci/ca) and stomatal number. Reciprocal transfer experiments of stomatal conductance showed that stomatal conductance in high-[CO2]-grown plants increased in comparison with ambient-[CO2]-grown plants when measured at their respective growth CO2 concentration and at the same measurement CO2 concentration (except a reduction in 700 μmol·mol-1 CO2 grown plants compared with plants on unchambered field when measured at growth CO2 concentration and 350 μmol·mol-1CO2). High-[CO2]-grown plants exhibited lower ci/ca ratios than ambient-[CO2]-grown plants when measured at their respective growth CO2 concentration. However, ci/ca ratios increased for plants grown in high CO2 concentrations compared with control plants when measured at the same CO2 concentration. There was no significant difference in stomatal number per unit long needle between elevated and ambient CO2. However, elevated CO2 concentrations reduced the total stomatal number of whole needle by the decline of stomatal line and changed the allocation pattern of stomata between upper and lower surface of needle.

Effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization in high myopia mice

AIM:To evaluate effects of endogenous dopamine induced by low concentration atropine eye drops on choroidal neovascularization(CNV)in high myopia mice.METHODS:The C57BL/6J mice were deprived of the right eye for 4wk,and the high myopia was diagnosed by optometry,the diopter was less than-6.00 D,and CNV was induced by 532 nm laser.The changes of dopamine D1 receptor(DRD1),dopamine D2 receptor(DRD2),and vascular endothelial growth factor A(VEGFA)were detected by Western blot technology at 0.5,1,2h,and 7d after 0.01%,0.05%,and 0.1%atropine eye drops,respectively,the area of CNV was measured.RESULTS:Significant increases were observed on the expression of DRD2 in mouse high myopia model at 0.5,1,2h,7d with 0.05%and 0.1%atropine eye drops(P<0.05).Significant decreases were observed on the expression of DRD1 and VEGFA in mouse high myopia model at 0.5,1,2h,7d with 0.05%and 0.1%atropine eye drops(P<0.05).The area of CNV induced by laser in the drug-treated group was significantly smaller than that in the control group,and the higher the concentration,the more significant the inhibitory effect(P<0.05).CONCLUSION:The 0.01%,0.05%,0.1%atropine eye drops can decrease the level of VEGFA and inhibit high myopia CNV indirectly by up-regulating the level of DRD2 and down-regulating the level of DRD1,and the effect of 0.05%and 0.1%atropine eye drops is more significant.

EXPERIMENTAL STUDIES ON FELDSPAR ORE CONCENTRATION

A series of Fe2O3-elimination experiments were conducted on feldspar samples from Tangshan Stone-powder Plant. These experimental methods include scrubbing desliming, flotation, rod milling and high gradient magnetic separation. Some technical factors of feldspar concentration and a new technological flow-sheet of ceramics raw material concentration were put forward.

Adapting Integrated High Concentrated PV Modules and Evacuated Tube Collectors to Minimize Building Energy Consumption in Hot Climate

Energy consumption in buildings is considered a significant portion of gross power dissipation, so a great effort is required to design efficient construction. In severe hot weather conditions as Kuwait, energy required for building cooling and heating results in a huge energy loads and consumption and accordingly high emission rates of carbon dioxide. So, the main purpose of the current work is to convert the existing institutional building to near net-zero energy building (nNZEB) or into a net-zero energy building (NZEB). A combination of integrated high concentrated photovoltaic (HCPV) solar modules and evacuated tube collectors (ETC) are proposed to provide domestic water heating, electricity load as well as cooling consumption of an institutional facility. An equivalent circuit model for single diode is implemented to evaluate triple junction HCPV modules efficiency considering concentration level and temperature effects. A code compatible with TRNSYS subroutines is introduced to optimize evacuated tube collector efficiency. The developed models are validated through comparison with experimental data available from literature. The efficiency of integrated HCPV-ETC unit is optimized by varying the different system parameters. Transient simulation program (TRNSYS) is adapted to determine the performance of various parts of HCPV-ETC system. Furthermore, a theoretical code is introduced to evaluate the environmental effects of the proposed building when integrated with renewable energy systems. The integrated HCPV-ETC fully satisfies the energy required for building lighting and equipment. Utilizing HCPV modules of orientation 25? accomplishes a minimum energy payback time of about 8 years. Integrated solar absorption chiller provides about 64% of the annual air conditioning consumption needed for the studied building. The energy payback period (EPT) or solar cooling system is about 18 years which is significantly larger than that corresponding to HCPV due to the extra expenses of solar absorption system. The life cycle savings (LCS) of solar cooling absorption system is approximately $2400/year. Furthermore, levelized cost of energy of solar absorption cooling is $0.21/kWh. Hence, the net cost of the solar system after subtracting the CO2 emission cost will be close to the present price of conventional generation in Kuwait (about $0.17/kWh). Finally, the yearly CO2 emission avoided is approximately 543 ton verifying the environmental benefits of integrated HCPV-ETC arrangements in Kuwait.

Environmental Impacts of Grid Connected High Concentrated Photovoltaic Systems Adapted for Peak Load Minimization in Hot Climate

High concentrated PV multi-junction solar cells (HCPV) likely present a favorable alternative to achieve low cost of energy. However, multi-junction solar cell has different characteristics which should be settled before they can be adapted for large scale energy generation. Peak energy consumption in Kuwait usually occurs in periods of utilizing air conditioning systems which are essentially used in almost all year around in harsh climate like Kuwait. Power consumed at peak times is more costly than power needed to satisfy loads at regular consumption times. The main goal of the present research is to increase HCPV solar cells’ efficiency, to decrease maximum power cost in Kuwait. Multi-junction solar cells performance in weather conditions of Kuwait is investigated employing a single diode equivalent circuit model. The model developed considers the impacts of concentration ratio as well as temperature. Most research in literature review usually neglects shunt resistance of the diode, however this resistance is taken into consideration in current developed theoretical model. To calibrate the present model, current predictions are compared with corresponding measured data provided by multi-junction solar cell manufacturer. The total root mean square errors in the present model predictions are about 1.8%. This means that current developed model of single diode model which takes into account shunt resistance impacts gives precise and reliable data. HCP electrical efficiency is noticed to rise as concentration increases but to a certain concentration value, then it begins to decrease. In addition, utilizing HCPV linked to grid satisfies great decrease in maximum load. Power produced from HCPV modules is utilized to provide energy needs to a family in normal Kuwaiti family home to evaluate HCPV environmental effects. HCPV modules slopes and areas are changed to accomplish peak energy production all over the year. Present results reveal that optimum power production corresponds to HCPV modules directed to south and having latitude of 25°. In addition, employing HCPV modules can avoid approximately 1.55 ton of emitted CO2 per year. In conclusion, current work reveals the advantage impacts of grid connected HCPV in Kuwait weather.

不同w(SiO_(2))铁精矿高温烧结性能研究与优化配矿

本文以新钢4种不同w(SiO_(2))的铁精矿为研究对象,深入探讨同化性能、液相流动性能、烧结体固结强度和铁酸钙生成特性等高温烧结性能,并以此为基础,结合现场生产方案进行优化配矿烧结试验。结果表明:在固定碱度为1.95的条件下,随着铁精矿中w(SiO_(2))提高,液相生成温度降低,液相生成量显著增加,液相流动性改善,但w(SiO_(2))过高会对同化性能和烧结体固结强度产生负面影响;合理调控w(SiO_(2))是优化烧结成矿过程的液相特性以及改善烧结矿质量的关键;通过优化精矿配比使含铁原料的w(SiO_(2))分数由3.90%提高至3.99%,烧结机利用系数提高0.25 t/(m^(2)·h),烧结矿成品率和转鼓强度分别提高5.91%和8.12%,固体燃料消耗则降低5.59 kg/t,烧结矿指标显著改善。

基于卷积神经网络的燃煤锅炉近壁区H_(2)S浓度分布实时预测模型

近年来,燃煤锅炉普遍采用空气分级燃烧技术以降低氮氧化物的排放.空气分级技术的核心是在炉内主燃区形成乏氧的还原性气氛,从而抑制氮氧化物的生成.但还原性气氛会导致强腐蚀性H_(2)S浓度的显著升高,增加了锅炉水冷壁的高温腐蚀风险.由于CFD数值模拟方法耗时较长,目前仍缺少一种能实时、准确地反映锅炉运行过程中近壁区H_(2)S浓度分布的技术手段.针对上述问题,本文首先构建了一个锅炉CFD数值计算模型,对某350MW超临界墙式对冲锅炉近壁区H_(2)S分布特性进行了数值模拟研究,锅炉出口参数及腐蚀位置与现场吻合良好.结果表明,空气分级燃烧技术下炉膛呈还原性气氛,底层对冲燃烧器的对撞气流对侧墙水冷壁的冲刷是造成锅炉侧墙近壁区H_(2)S高浓度的原因.随后,以锅炉的各项运行参数为输入,以近壁区H_(2)S浓度分布图像为输出,构建转置卷积神经网络.基于提出的H_(2)S浓度预测数值模型,搭建了包含120个不同运行工况的数据库,对神经网络进行训练、验证和测试.结果表明,神经网络测试集预测结果与CFD模型预测结果符合良好,30%Local MAPE仅为1.06%,且计算时长在0.1 s以内,实现了燃煤锅炉近壁区H_(2)S浓度分布的实时预测.

催化反应角度的非衡态高浓度SO_(2)转化工艺分析

非衡态高浓度SO_(2)转化工艺为了满足工艺要求的转化率,对催化剂的选型和装填量设计提出了较高要求。从催化反应和转化角度,研究了转化一段的催化剂装填量、进气量、进口烟气温度对出口烟气温度与转化率的影响,认为进口烟气温度对出口烟气温度的影响非常显著,并对催化剂选型和装填方案、进口烟气条件和温度分布提出了相应的建议。

高SO_(2)浓度烟气超低排放治理技术和方法

以石墨化炉高SO_(2)浓度烟气为例,采用石灰-石膏脱硫工艺,优化设计了双塔双循环、低烟气流速、高液气比、增效托盘、高效管束式除雾器等新技术和方法,实现烟气超低排放,为其他行业高SO_(2)浓度烟气超低治理提供了可靠的参考,具有重要的借鉴意义。

高CO_2浓度下豆科4种乔木幼苗的生理生化反应

本文对４种豆科乔木幼苗在高ＣＯ２浓度（５５０×１０－６±５０×１０－６）和在对照ＣＯ２浓度（约为３５０×１０－６）下生长的幼苗的一些生理生化指标进行了比较研究。初步结果显示：高ＣＯ２浓度能缩短幼苗子叶的存活时间。高ＣＯ２环境下生长的４种幼苗叶片中的可溶性蛋白、可溶性糖、纤维素、Ｎ、Ｐ、Ｋ、Ｍｇ的含量（均为全量）较对照ＣＯ２环境下生长的幼苗的相应值低，而淀粉含量则较高。其中以全氮、可溶性糖差异较显著。以单位鲜重表示的幼苗叶片叶绿素（Ｃｈｌ）和类胡萝卜素（Ｃａｒ）含量降低。高ＣＯ２浓度下生长的４种幼苗（３０天龄）叶片中硝酸还原酶活性比对照ＣＯ２浓度下生长的幼苗的值低。高ＣＯ２浓度下生长的４种幼苗叶片的平均蒸腾速率有不同程度的降低，而气孔阻力升高。幼苗对高ＣＯ２环境的反应与种的生态特性有关。喜光的大叶合欢幼苗对高ＣＯ２环境的反应较大，喜光而具一定耐荫性的猴耳环幼苗次之。

花岗质熔体中SnO_2含量与结晶温度和时间的关系

锡石在花岗质熔体中的溶解度 ,是阐明花岗岩全岩型锡矿成因的关键。文章设计了以结晶温度和结晶时间为参数的两组熔化_结晶实验 ,试图模拟锡石在岩浆结晶分异过程中的动态变化 ,并在花岗岩_HF_H2 O体系的高温高压实验结果基础上 ,讨论花岗质熔体中SnO2 含量与结晶温度和时间的关系。实验结果表明 :①在岩浆条件下可以形成锡石 ;②随着结晶温度的降低和时间的加长 ,熔体中SnO2 含量先升高后降低 ,表明其经历了由不饱和到过饱和 。

高钾离子引起PC12细胞内游离Ca^(2+)浓度升高的机制

目的：分析高钾离子（Ｋ＋）引起ＰＣ１２细胞内游离钙离子浓度（［Ｃａ２＋］ｉ）升高的可能机制。方法：利用ＭｉｒａＣａｌＩｍａｇｅＳｙｓｔｅｍ检测［Ｃａ２＋］ｉ，Ｃａ２＋荧光探针为Ｆｕｒａ－２／ＡＭ。结果：（１）ＫＣｌ浓度为３０～１００ｍｍｏｌ／Ｌ时，可剂量依赖性地诱导ＰＣ１２细胞［Ｃａ２＋］ｉ升高；（２）在细胞外无Ｃａ２＋时，高Ｋ＋对ＰＣ１２细胞［Ｃａ２＋］ｉ无影响；（３）Ｌ－型电压门控钙通道阻滞剂维拉帕米、地尔硫和硝苯地平的浓度分别为５×１０－５，１×１０－４和５×１０－３ｍｏｌ／Ｌ时，可完全阻断高Ｋ＋诱导的ＰＣ１２细胞［Ｃａ２＋］ｉ升高，但Ｎ－型电压门控钙通道阻滞剂ω－ｃｏｎｏｔｏｘｉｎＧＶＩＡ在浓度为１×１０－６ｍｏｌ／Ｌ时，对高Ｋ＋诱导的ＰＣ１２细胞［Ｃａ２＋］ｉ升高没有影响；（４）５×１０－５ｍｏｌ／Ｌ维拉帕米对细胞外由无Ｃａ２＋到有Ｃａ２＋过程引起的［Ｃａ２＋］ｉ升高无抑制作用。结论：高Ｋ＋引起ＰＣ１２细胞［Ｃａ２＋］ｉ升高以细胞质膜上Ｌ－型电压门控Ｃａ２＋通道开放为基础。

CO_2和温度升高及干旱对小麦叶片化学成分的影响

研究了 CO2 浓度升高、高温和干旱对干旱区小麦叶片化学成分的影响 ,结果表明 :CO2 浓度升高时各化学成分之间的差异只有在 40 %田间持水量时才表现显著 ,说明未来 CO2 浓度升高对干旱区小麦化学成分的影响可能大于在非干旱区的影响 ;CO2 浓度升高可减小因为土壤水分不同而造成的小麦化学成分之间的差异 ;高温对小麦化学成分的主要影响是引起 N含量的显著降低 ;CO2 浓度升高、高温和干旱三因子对干旱区小麦化学成分的复合影响是 N含量下降和 C/ N的显著上升 。

高糖对线粒体乙醛脱氢酶2在大鼠心肌成纤维细胞中表达的影响

目的:观察心肌成纤维细胞是否存在线粒体乙醛脱氢酶2(ALDH2)的表达,探讨ALDH2在高糖诱导的心肌成纤维细胞引起纤维化发生中的作用。方法:原代培养心肌成纤维细胞,分为正常对照组(5.5 mmol/L)、正常+ALDH2激动剂Alda-1(20μmol/L)组、高糖组(30 mmol/L)、高糖+Alda-1组。免疫荧光鉴定心肌成纤维细胞。各组细胞分别培养48 h后应用MTT法检测成纤维细胞增殖活力,RT-PCR和Western blot检测ALDH2 m RNA及蛋白的表达。结果:RT-PCR和Western blot结果显示心肌成纤维细胞ALDH2 m RNA和蛋白均有表达。与正常对照组相比,高糖组心肌成纤维细胞增殖能力提高(P<0.01),ALDH2蛋白表达下降(P<0.05);与高糖组相比,高糖+Alda-1组心肌成纤维细胞增殖能力降低(P<0.01),ALDH2的蛋白表达增加(P<0.05)。结论:心肌成纤维细胞存在ALDH2的表达,ALDH2激动剂Alda-1提高ALDH2的表达后可以抑制高糖引起的心肌成纤维细胞的增殖。

高浓度发酵及膜分离技术在2-酮基-D-葡萄糖酸生产中的应用研究

研究中和剂和底物总浓度对2-酮基-D-葡萄糖酸补料分批发酵的影响,并初步考察膜分离技术在发酵产物提取中应用的可行性。结果表明:在2-酮基-D-葡萄糖酸的补料分批发酵中,以NaOH或Na2CO3代替CaCO3作为中和剂,能够有效提高发酵培养基中的底物总浓度,且发酵转化率可达90%左右;在NaOH或Na2CO3作为发酵中和剂的情况下,膜技术可应用于2-酮基-D-葡萄糖酸的提取中,且有助于其提取率的提高。

不同浓度5-氨基酮戊酸光动力疗法治疗CIN1/2伴HR-HPV感染患者的效果比较

目的分析不同浓度5-氨基酮戊酸(5-ALA)光动力疗法治疗宫颈上皮内瘤变(CIN)1/2伴高危型人乳头状瘤病毒(HR-HPV)感染患者的临床效果。方法选取2017年1月—2019年6月江苏省宜兴市人民医院就诊的80例CIN1/2伴HR-HPV感染患者为研究对象,按照随机数字表法将其分为观察组和对照组,每组40例。对照组给予低浓度5-ALA,观察组采用高浓度5-ALA治疗,比较两组治疗后3、6个月宫颈轻度异常或正常人数、HR-HPV转阴率、白细胞介素-6(IL-6)、肿瘤坏死因子-α(TNF-α)水平及不良反应发生情况。结果治疗后3、6个月,两组CIN1患者宫颈轻度异常或正常例数及HR-HPV DNA转阴率比较,差异无统计学意义(P>0.05);观察组CIN2患者宫颈轻度异常或正常例数、HR-HPV DNA转阴率高于对照组CIN2患者(P<0.05)。治疗后3个月,两组IL-6水平高于治疗前、TNF-α水平低于治疗前;观察组IL-6水平高于对照组,TNF-α水平低于对照组(均P<0.05)。所有患者均未出现继发感染、出血、宫颈管狭窄或瘢痕形成。结论高浓度5-ALA光动力疗法治疗CIN1/2伴HR-HPV感染患者的临床效果显著,可有效提高HR-HPV转阴率,同时调节炎症因子水平,提高患者细胞免疫水平。

高糖通过环加氧酶2依赖性途径诱导GRP78表达改变

目的:观察高糖慢性处理对血管内皮细胞内质网应激标志蛋白葡萄糖调节蛋白78(GRP78)表达的影响及其作用机制。方法:培养的HUVECs细胞用含正常糖(5.5mmol/L)或高糖(30mmol/L)的培养基处理不同时间后,用MTT法测定细胞存活率,流式细胞仪测定细胞凋亡,Western blotting法测定蛋白表达情况。结果:与相应对照组相比,HUVECs细胞经高糖孵育24-48h后,GRP78蛋白表达量先增加后减少;而环加氧酶-2(COX-2)蛋白表达量逐渐增加。COX-2选择性抑制剂尼美舒利与高糖共孵育后,可明显抑制高糖引起的GRP78蛋白表达改变;同时尼美舒利可抑制高糖孵育48h后诱导的细胞凋亡。结论:高糖慢性处理可诱导HUVECs细胞GRP78表达先增加后减少,此过程依赖于COX-2蛋白的上调。