Asymmetric expression of CA2 and CA13 linked to calcification in the bilateral mandibular condyles cause crossed beaks in chickens

Crossed beak is a complex mode of inheritance with prevalence ranging from 0.2 to 7.4% in at least 12 chicken strains worldwide.To reveal the intrinsic factors causing crossed beaks,genes expression patterns in bilateral mandibular condyle between affected and normal birds were characterized by RNA sequencing analysis in the present studies.Crossed beak was induced by short length of unilateral mandibular ramus,and a total of 110differentially expressed genes were up-or down-regulated in the affected(short)mandibular condyle side as compared to the normal side.Carbonic anhydrase 2(CA2)and Carbonic anhydrase 13(CA13)were enriched in the carbonate dehydratase activity,and high-expressed in mandibular condyle and osteoblasts(P<0.05).However,both were low-expressed in short mandibular condyle side of affected birds(P<0.05).The carbonate dehydratase inhibitor experiments confirmed that there is positive association between the calcification and carbonic anhydrase isoenzymes.Quantitative analysis with cetylpyridinium chloride showed a decrease in calcification when the cells were transfected with an anti-CA13 shRNA.Our research suggested that CA2 and CA13 are down-calcified in shortside mandibular condyle,and caused mandibular ramus to grow slowly.CA2 and CA13 have the critical role in crossed beaks by regulating calcification of mandibular condyle.

大豆异黄酮通过抑制Wnt/Ca2+信号通路减轻大鼠脑缺血再灌注引起的钙超载

目的 探讨大豆异黄酮(SI)减轻脑缺血再灌注(I/R)引起钙超载的作用机制。方法 将48只SD大鼠采用随机数法分为4组:假手术组(Sham组)、脑缺血再灌注模型组(I/R组)、病毒空载组(NC组)、Frizzled-2敲低组(Knock down组),12只/组。采用线栓法堵塞大脑中动脉2 h,再灌注24 h构建I/R模型。采用Western blot验证病毒敲低效率并检测Wnt/Ca2+信号通路相关蛋白Wnt5a、Frizzled-2和P-CaMKⅡ的变化。采用钙含量显色法检测各组缺血半暗带(IP)区钙离子浓度变化,HE检测各组IP区组织结构变化。另将72只SD大鼠采用随机数法分为3组:Sham组、I/R组、大豆异黄酮预处理组(SI组),24只/组。采用多普勒血流仪检测局部脑血流变化,TTC染色检测脑梗死体积,HE和尼氏染色检测IP区组织变化、免疫荧光检测ROS、Ca2+和细胞凋亡水平、流式检测细胞钙离子浓度,试剂盒检测血清MDA和SOD水平,Western blotting和免疫组化检测IP区Wnt5a、Frizzled-2和P-CaMKⅡ蛋白表达。结果 与I/R组比较,Knock down组钙离子浓度(P<0.001)、Wnt5a(P<0.05)、Frizzled-2(P<0.05)和P-CaMKⅡ(P<0.001)表达水平均降低;与I/R组比较,SI组钙离子浓度(P<0.05)、ROS和MDA水平(P<0.001)、细胞凋亡程度(P<0.001)、脑梗死体积(P<0.001)、Wnt5a、Frizzled-2和P-CaMKⅡ表达水平(P<0.05)均降低,SOD水平升高(P<0.001)。结论大豆异黄酮可能通过抑制Wnt/Ca2+信号通路减轻大鼠脑缺血再灌注引起的钙超载。

腹部推拿对UC模型大鼠背根神经节PLC/IP3R/Ca2+信号通路及AKT、p-AKT蛋白表达的影响

目的:观察腹部推拿干预溃疡性结肠炎(UC)模型大鼠后,对大鼠背根神经节PLC/IP3R/Ca^(2+)信号通路及AKT、p-AKT蛋白表达的影响,从而探讨腹部推拿对溃疡性结肠炎内脏高敏感的作用机制。方法:将36只SPF级大鼠分成空白组、模型组、推拿组、美沙拉嗪组4组,除空白组自由饮用蒸馏水外,其余各组采用自由饮5%葡聚糖硫酸钠溶液(DSS)的方法制备大鼠UC模型。造模第2日起推拿组采用腹部推拿进行干预,美沙拉嗪组进行美沙拉嗪溶液进行灌胃,空白组、模型组仅俯卧位束缚固定于固定器中。干预15日后,采用邻-甲酚酞络合铜比色法检测背根神经节(DRG)细胞钙离子浓度;ELISA法检测DRG组织中磷脂酶C(PLC)、肌醇1,4,5-三磷酸(IP3)、肌醇1,4,5-三磷酸受体(IP3R)的表达,WesternBlot检测DRG组织中蛋白激酶B(AKT)、磷酸化蛋白激酶B(p-AKT)蛋白表达。结果:与模型组比较,推拿组大鼠DRG细胞Ca^(2+)浓度和DRG组织中IP3、IP3R含量呈降低趋势,其中DRG细胞Ca^(2+)浓度有显著差异(P<0.01),其他指标的组间差异无统计学意义(P>0.05);推拿组DRG组织中PLC含量及AKT、p-AKT蛋白表达呈增加趋势,但差异无统计学意义(P>0.05)。结论:腹部推拿抑制UC内脏高敏感性,其作用机制可能与抑制PLC-IP3R-Ca^(2+)信号通路和促进UC大鼠背根神经节AKT激活有关。

Ca2+/calmodulin-dependent protein kinase II regulates colon cancer proliferation and migration via ERK1/2 and p38 pathways

AIM To investigate the role of calmodulin-dependent protein kinase Ⅱ(Ca MKⅡ) in colon cancer growth,migration and invasion.METHODS Ca MKⅡ expression in colon cancer and paracancerous tissues was evaluated via immunochemistry. Transcriptional and posttranscriptional levels of Ca MKⅡin tissue samples and MMP2,MMP9 and TIMP-1 expression in the human colon cancer cell line HCT116 were assessed by q RTPCR and western blot. Cell proliferation was detected with the MTT assay. Cancer cell migration and invasion were investigated with the Transwell culture system and woundhealing assay.RESULTS We first demonstrated that CaMK Ⅱ was ove rexpressed in human colon cancers and was associated with cancer differentiation. In the human colon cancer cell line HCT116,the Ca MKII-specific inhibitor KN93,but not its inactive analogue KN92,decreased cancer cell proliferation. Furthermore,KN93 also significantly prohibited HCT116 cell migration and invasion. The specific inhibition of ERK1/2 or p38 decreased the proliferation and migration of colon cancer cells.CONCLUSION Our findings highlight Ca MKⅡ as a potential critical mediator in human colon tumor development and metastasis.

Mitofusin-2 mediated mitochondrial Ca2+ uptake 1/2 induced liver injury in rat remote ischemic perconditioning liver transplantation and alpha mouse liver-12 hypoxia cell line models

AIM To investigate the protective mechanism of mitofusin-2(Mfn2) in rat remote ischemic perconditioning(RIC) models and revalidate it in alpha mouse liver-12(AML-12) hypoxia cell lines.METHODS Sprague-Dawley rats were divided into three groups(n = 6 each): sham, orthotopic liver transplantation and RIC. After operation, blood samples were collected to test alanine aminotransferase and aspartate aminotransferase. The liver lobes were harvested for histopathological examination, western blotting(WB) and quantitative real-time(q RT)-PCR. AML-12 cell lines were then subjected to normal culture, anoxic incubator tank culture(hypoxia) and anoxic incubator tank culture with Mfn2 knockdown(hypoxia + Si), and data of q RT-PCR, WB, mitochondrial membrane potential(ΔΨm), apoptosis, endoplasmic reticulum Ca2+ concentrations and mitochondrial Ca2+ concentrations were collected.RESULTS Both sham and normal culture groups showed no injury during the experiment. The RIC group showed amelioration of liver function compared with the orthotopic liver transplantation group(P < 0.05). q RTPCR and WB confirmed that Mfn2-mitochondrial Ca2+ uptake 1/2(MICUs) axis was changed(P < 0.005). In AML-12 cell lines, compared with the hypoxia group, the hypoxia + Si group attenuated the collapse of ΔΨm and apoptosis(P < 0.005). The endoplasmic reticulum Ca2+ decrease and mitochondrial Ca2+ overloading observed in the hypoxia group were also attenuated in the hypoxia + Si group(P < 0.005). Finally, q RT-PCR and WB confirmed the Mfn2-MICUs axis change in all the groups(P < 0.005).CONCLUSION Mfn2 participates in liver injury in rat RIC models and AML-12 hypoxia cell lines by regulating the MICUs pathway.

Synthesis and characterization of Ca2Sn1-xCexO4 with blue luminescence originating from Ce^4＋ charge transfer transition

Ce^4＋-doped Ca2SnO4 with a one-dimensional structure, which emits bright blue light, is prepared by using a solid-state reaction method. The x-ray diffraction results show that the Ce^4＋ ions doped in Ca2SnO4 occupy the Sn^4＋ sites. The excitation and emission spectra of Ca2Sn1-xCexO4 appear to have broad bands with peaks at - 268nm and -442nm, respectively. A long excited-state lifetime （-83μs） for the emission from Ca2Sn1-xCexO4 suggests that the luminescence originates from a ligand-to-metal Ce^4＋ charge transfer （CT）. The luminescent properties of Ca2Snl_xCexO4 have been compared with those of Sr2CeO4, which is the only material reported so far to show Ce^4＋ CT luminescence. More interestingly, it is observed that the emission intensity of Ca2Sn1-xCexO4 with a small doping concentration （x - 0.03） is comparable to that of Sr2CeO4 in which the concentration of active centre is 100%.

Evidence for Multiple Underlying Fermi Surface and Isotropic Energy Gap in the Cuprate Parent Compound Ca2CuO2Cl2

The parent compounds of the high-temperature cuprate superconductors are Mott insulators.It has been generally agreed that understanding the physics of the doped Mott insulators is essential to understanding the mechanism of high temperature superconductivity.A natural starting point is to elucidate the basic electronic structure of the parent compound.Here we report comprehensive high resolution angle-resolved photoemission measurements on Ca_2CuO_2Cl_2,a Mott insulator and a prototypical parent compound of the cuprates.Multiple underl.ying Fermi surface sheets are revealed for the first time.The high energy waterfall-like band dispersions exhibit different behaviors near the nodal and antinodal regions.Two distinct energy scales are identified：a d-wave-like low energy peak dispersion and a nearly isotropic lower Hubbard band gap.These observations provide new information of the electronic structure of the cuprate parent compound,which is important for understanding the anomalous physical properties and superconductivity mechanism of the high temperature cuprate superconductors.

CA2、CA9蛋白在舌鳞状细胞癌的表达及预后价值

目的探讨CA2、CA9蛋白在舌鳞状细胞癌(TSCC)中的表达及生存意义,并分析两者表达相关性及在癌症中的潜在机制。方法UCSC Xena在线分析CA2、CA9 mRNA在TSCC和对应正常组织中的表达,免疫组化验证CA2、CA9蛋白在89例TSCC及29例癌旁正常组织中的表达,并分析CA2、CA9蛋白表达相关性及其与临床因素相关性,同时研究了CA2、CA9对TSCC的诊断及生存意义。最后用STRING和Metascape数据库进一步探索了CA2和CA9蛋白潜在作用机制。结果与癌旁正常组织相比,UCSC Xena数据库显示CA2、CA9 mRNA在TSCC中均高表达(均P<0.05),同时免疫组化实验表明CA2、CA9蛋白在TSCC中也显著高表达(均P<0.05)。其中,CA2蛋白在TSCC中高表达率为21.35%,CA9高表达率达61.80%。CA2蛋白高表达与TSCC更好的分化程度相关(P<0.05),CA9过度表达与更差的T分期明显相关(P<0.05),且CA2与CA9蛋白表达呈正相关(r=0.240,P<0.05)。CA2、CA9蛋白在TSCC中的ROC曲线下面积分别为83.9%、85.8%,且两者过度表达均与患者的不良预后相关(均P<0.05)。COX多因素模型提示CA9过度表达可能是TSCC预后不良的独立因素(HR:2.748,P<0.05)。CA2、CA9可能参与了调节pH、缺氧反应等生物过程。结论CA2、CA9蛋白高表达提示TSCC患者的预后不良。

Adsorption equilibrium, kinetics, and dynamic separation of Ca2+ and Mg2+ ions from phosphoric acid–nitric acid aqueous solution by strong acid cation resin

The separation of Ca2+and Mg2+ions from phosphoric acid-nitric acid aqueous solution is very significant for the neutralization process of nitrophosphate fertilizer.This paper studied the adsorption equilibrium,kinetics,and dynamic separation of Ca2+and Mg2+ions by strong acid cation resin,and the effects of phosphoric acid and nitric acid on the adsorption process were investigated.The results reveal that the adsorption process of Ca2+and Mg2+ions in pure water on resin is in good agreement with the Langmuir isotherm model and their maximal adsorption capacities are 1.86 mmol·g-1 and 1.83 mmol·g-1,respectively.The adsorption kinetics of Ca2+and Mg2+ions on resin fits better with the pseudo-first-order model,and the adsorption equilibrium in pure water is reached within 10 min contact time,while at the present of phosphoric acid,the adsorption rate of Ca2+and Mg2+ions on resin will go down.The dynamic separation experiments demonstrate that the designed column adsorption is able to undertake the separation of metal ions from the mix acids aqueous solution,but the dynamic operation should control the flow rate of mix acid solution.Besides nitric acid solution was proved to be effective to completely regenerate the spent resin and achieve the recyclable operation of separation process.

Ca2+依赖的膜结合蛋白7在胃癌中的表达及临床意义

目的:探讨Ca2+依赖的膜结合蛋7(CPNE7)在胃癌中的表达水平及其与肿瘤发生发展的关系。方法:首先通过生物信息学分析CPNE7在胃癌及癌旁中的表达差异及其与预后的关系。收集2020年1月至2021年5月在兰州大学附属第二医院行手术治疗的102例胃癌患者的癌组织及其癌旁组织,制作成组织芯片(TMA),采用免疫组织化学染色法检测CPNE7的表达水平,Spearman相关分析CPNE7表达与胃癌患者临床病理特征的关系。采用RT-PCR和Western blot检测CPNE7在胃癌细胞(MKN45/AGS/HGC-27)和人正常胃黏膜细胞(GES-1)中mRNA和蛋白的表达水平。结果:CPNE7蛋白及其mRNA水平在胃癌中高于癌旁组织(P<0.05),CPNE7的表达与患者的临床分期(P<0.001)、T分期(P=0.012)、N分期(P=0.01)以及有无淋巴结浸润(P=0.005)和Lauren’s分型(P=0.007)显著相关,与年龄(P=0.37)、性别(P=0.121)、分化程度(P=0.15)、有无转移(P=0.835)、血管浸润(P=0.275)、神经浸润无相关(P=0.814)。结论:CPNE7在胃癌组织和细胞中呈高表达,其表达与临床分期、T分期、N分期、淋巴结浸润和Lauren’s分型相关,提示CPNE7可能参与胃癌的发生发展,有望成为胃癌的诊断标志物。

Ca2+ influx and ROS generation trigger CDDO-Me-induced dilation of the ER and apoptosis in breast cancer cells

OBJECTIVE The synthetic triterpenoid 2-cyano-3,12-dioxoolean-1,9(11)-dien-C28-methyl ester(CDDO-Me)is considered a promising anti-tumorigenic compound.In this study,we investigated the anti-cancer effect of CDDO-Me on breast cancer cells and its underlying mechanisms.METHODS To investigate the effect of CDDO-Me on various breast cancer cells,cell viability assay using calcein-AM and EthD-1 as well as MTT assay was performed.To clarify the origin of CDDO-Me-induced vacuoles,electron microscopy as well as fluorescence microscopy using YFP-ER or YFP-Mito construct was performed.To measure the changes in intracellular Ca2+and ROS levels,flow cytometry using Fluo-3 and H2DCF-DA was performed.RESULTS CDDO-Me treatment induces progressive ER-derived vacuolation and subsequent apoptosis in various breast cancer cells.CDDO-Me-induced increases in intracellular Ca2+ levels,reflecting influx from the extracellular milieu,make a critical contribution to ER-derived vacuolation and subsequent cell death.In parallel with increasing 2+ Calevels,CDDO-Me markedly increases the generation of reactive oxygen species(ROS).Interestingly,we found that there exists a reciprocal positive-regulatory loop between Ca2+ influx and ROS generation that triggers ER stress and ER dilation in response to CDDO-Me.CONCLUSION ER-derived vacuolation via Ca2+ influx and ROS generation is responsible for the potent anticancer effects of CDDOMe on breast cancer cells.

The cloning of Na+/Ca2+exchaanger Gene and its expression in brain ischemia

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Intestinal Ca2+ absorption revisited: A molecular and clinical approach

Ca2+has an important role in the maintenance of the skeleton and is involved in the main physiological processes.Its homeostasis is controlled by the intestine,kidney,bone and parathyroid glands.The intestinal Ca2+absorption occurs mainly via the paracellular and the transcellular pathways.The proteins involved in both ways are regulated by calcitriol and other hormones as well as dietary factors.Fibroblast growth factor 23(FGF-23)is a strong antagonist of vitamin D action.Part of the intestinal Ca2+movement seems to be vitamin D independent.Intestinal Ca2+absorption changes according to different physiological conditions.It is promoted under high Ca2+demands such as growth,pregnancy,lactation,dietary Ca2+deficiency and high physical activity.In contrast,the intestinal Ca2+transport decreases with aging.Oxidative stress inhibits the intestinal Ca2+absorption whereas the antioxidants counteract the effects of prooxidants leading to the normalization of this physiological process.Several pathologies such as celiac disease,inflammatory bowel diseases,Turner syndrome and others occur with inhibition of intestinal Ca2+absorption,some hypercalciurias show Ca2+hyperabsorption,most of these alterations are related to the vitamin D endocrine system.Further research work should be accomplished in order not only to know more molecular details but also to detect possible therapeutic targets to ameliorate or avoid the consequences of altered intestinal Ca2+absorption.

Critical behavior and effect of Sr substitution in double perovskite Ca2CrSbO6

The double perovskite Ca2CrSbO6 exhibits a ferromagnetic long-range order below Tc=13 K and a saturation magnetization of 2.35µB at 2 K.In this study,the polycrystalline Ca2CrSbO6 is synthesized under high pressure and high temperature,and the critical behavior of the ferromagnetic material as well as the effects of the magnetic behavior due to the isovalent substitution of Sr2+for Ca2+is investigated.Also studied are the ferromagnetic criticality of the double perovskite Ca2CrSbO6 at the ferromagnetic transition temperature Tc≈12.6 K from the isotherms of magnetization M(H)via an iteration process and the Kouvel–Fisher method.The critical exponents associated with the transition are determined as follows:β=0.322,γ=1.241,andδ=4.84.The magnetization data in the vicinity of Tc can be scaled into two universal curves in the plot of M/|ε|βversus H/|ε|β+γ,whereε=T/Tc−1.The obtainedβandγvalues are consistent with the predicted values from a three-dimensional Ising model.The effects of Sr substitution on the double perovskite Ca2CrSbO6 are taken into consideration.As the Sr content increases,the(Ca2−xSrx)CrSbO6 polycrystal shows a continuous switch from ferromagnetic to antiferromagnetic behavior.

Correlation of large conductance Ca2+ activated K+ channelα andβ subunit expression in uterine smooth muscle with the postpartum hemorrhage induced by uterine inertia

Objective:To study the correlation of large conductance Ca2+ activated K+ channel (BKCa)α andβ subunit expression in uterine smooth muscle with the postpartum hemorrhage induced by uterine inertia.Methods: The puerperae who underwent cesarean section and had postpartum hemorrhage induced by uterine inertia in Panzhihua Women and Children Health Hospital between March 2015 and May 2017 were selected as the hemorrhage group of the study, and the puerperae who underwent cesarean section and were without postpartum hemorrhage in Panzhihua Women and Children Health Hospital during the same period were selected as the control group. Proper amount of uterine muscle tissue was collected during the cesarean section to measure the expression of BKCaα andβ subunits and the levels of contraction-related proteins in uterine muscle as well as the contraction characteristic parameters of the uterine muscle.Results: The mRNA expression and protein expression of BKCaα andβ subunits in uterine muscle tissue of hemorrhage group were significantly higher than those of control group;the contraction amplitude, contraction frequency and contraction activity of uterine muscle tissue as well as the OTR, COX2, CX43 and HSP27 levels in uterine muscle tissue of hemorrhage group were significantly lower than those of control group;the BKCaα andβ subunit expression in uterine muscle tissue of hemorrhage group were negatively correlated with the contraction amplitude, contraction frequency and contraction activity as well as the OTR, COX2, CX43 and HSP27 levels.Conclusion: The high expression of BKCa in uterine smooth muscle can reduce the uterine muscle contractility and decrease the levels of contraction-related proteins, and it is closely related to the occurrence of postpartum hemorrhage induced by uterine inertia.

Relationship between serum Ca2+ level and nerve injury as well as myocardial injury in children with febrile convulsion

Objective:To study the relationship between serum Ca2+ level and nerve injury as well as myocardial injury in children with febrile convulsion.Methods: A total of 32 children with febrile convulsion treated in our hospital between May 2011 and September 2015 were selected as observation group and 30 healthy children receiving vaccination in our hospital during the same period were selected as normal control group. Blood calcium levels of two groups of children were detected, and the median blood calcium level was referred to further divide the observation group into high blood Ca2+ group (n=16) and low blood Ca2+ group (n=16). The differences in nerve injury and myocardial injury were compared between children with blood calcium levels within observation group.Results: Serum Ca2+ level of observation group was lower than that of normal control group;excitatory amino acids Glu, Asp, Lys and Ser contents in peripheral blood of low blood Ca2+ group were higher than those of high blood Ca2+ group while inhibitory amino acids Gly and GABA contents were lower than those of high blood Ca2+ group;cardiac function parameters SV, CI and Vpk levels of low blood Ca2+ group were lower than those of high blood Ca2+ group while SVR level was higher than that of high blood Ca2+ group;myocardial enzyme spectrum indexes CK-MB, LDH andα-HBDH contents in peripheral blood of low blood Ca2+ group were higher than those of high blood Ca2+ group.Conclusion: Serum Ca2+ level is low in children with febrile convulsion and Ca2+ level is negatively correlated with nerve injury and myocardial injury.

Kainate receptors in the CA2 region of the hippocampus

The hippocampus is involved in important brain functions such as learning and memory,spatial navigation,fear processing,and social behavior(Dudek et al,2016).The most prominent areas of the hippocampus are typically denoted as the dentate gyrus and the three areas of the cornu ammonis(CA1,CA2,and CA3).Discovered by Lorente de Nó(1934),the CA2 region of the hippocampus is a relatively small area interposed between CA3 and CA1 that forms the nexus linking the input of the entorhinal cortex to the output of CA1(Chevaleyre and Siegelbaum,2010).

不同水平钙肥对设施生姜生长、产量和根茎品质的影响

以莱芜大姜为试材,通过温室盆栽试验,采用根际增施的方法研究2.5、5.0、7.5、10.0、12.5 g·株^(-1)5个不同水平Ca(NO_(3))_(2)对生姜生长、产量及品质的影响。结果表明,增施外源Ca(NO_(3))_(2)促进了生姜的生长,提高了叶片色素含量、净光合速率及根茎的产量和品质。其中Ca(NO3)2施用量≥7.5 g·株^(-1)时与不施钙(CK)相比对生姜有显著的促长增产和提质作用,在10.0 g·株^(-1)时效果最显著,采收期生姜叶片叶绿素含量和光合速率较CK显著提高21.44%和34.37%,单株产量显著增加44.22%;可溶性糖、可溶性蛋白、游离氨基酸及维生素C含量分别显著提高28.13%、36.52%、19.15%和17.49%。Ca(NO_(3))_(2)施入量在12.5 g·株^(-1)时促进作用减弱。综上所述,试验范围内外源Ca(NO_(3))_(2)均促进了生姜生长和产量增加,改善了生姜根茎品质,以外源钙施用量为10.0 g·株^(-1)时,更利于提高生姜产量和品质。

Experimental and numerical studies of Ca(OH)_(2)/CaO dehydration process in a fixed-bed reactor for thermochemical energy storage

The Ca(OH)_(2)/CaO thermochemical energy storage(TCES)system based on calcium looping has received extensive attention owing to its high energy storage density,prolonged energy storage time,and environmental friendliness.The heat storage process of the Ca(OH)_(2)/CaO TCES system in a mixed heating reactor was evaluated in this study,by employing a combination of direct and indirect heating modes.The dehydration process was studied experimentally,and a numerical model was established and verified based on the experimental results.The dehydration behavior of 500 g of Ca(OH)_(2) powder was investigated in a fixed-bed reactor with mixed heating.The experimental and simulation results indicated that mixed heating causes combined centripetal and horizontal propulsion.Heat input is the main limiting factor in the heat storage process,because the radial advance of the reaction is hindered by the low thermal conductivity of the solid reactant particles.Heat transmission partitions were added to enhance the performance of the reactor.The performance of the modified reactor was compared with that of a conventional reactor.The radial heat transmission partitions in the modified reactor effectively enhance the energy storage rate and reduce the reaction time by 59.5%compared with the reactor without partitions.

Experimental study on the desulfurization and evaporation characteristics of Ca(OH)_(2) droplets

The experiments were conducted to focus on the desulfurization and evaporation characteristics of lime slurry droplets at 298-383 K. We designed an evaporation-reaction chamber with quartz glass windows.The monodisperse slurry droplet stream was injected into the evaporation reaction chamber, and the inlet gas components(air, air + SO_(2)) were introduced into the chamber. We applied the magnified digital in-line holography to measure the droplet parameters and calculated the evaporation rate. The effects of temperature, droplet concentration, and SO_(2) concentration on the evaporation rate of Ca(OH)_(2) droplets were discussed. Moreover, the Ca(OH)_(2) droplets under different experimental conditions were sampled,and the droplets were observed and analyzed using an off-line microscope. The evaporation rate of the Ca(OH)_(2) droplet increased at first, and then decreased during the falling process, and remained constant at last. The average evaporation rate of the Ca(OH)_(2) droplets increased significantly with the temperature increasing.