准东煤灰渣烧结熔融过程中钠基化合物作用机理研究

将Na₂CO₃添加剂按折算为Na₂O以20%的比例掺入煤灰中制成混合灰样,对混合灰样在不同温度下烧结.对不同温度下的烧结灰进行EDS元素分析和XRD物相分析,探究钠基化合物在准东煤灰烧结过程中的转变机理.并以EDS分析结果为基础用Fact sage 5.2计算软件中的Equilib模块进行化学热力学平衡反应计算.结果表明,随着烧结温度的升高,硫会发生富集,而钠主要和硫反应生成Na₂SO₄.同时会有NaCl的产生,NaCl会与含钾化合物反应置换出KCl.NaCl、KCl和Na₂SO₄与其他物质产生低温共熔物.     

碳酸钠对选择性非催化还原反应影响的研究

在管式石英反应器中研究了Na₂CO₃对氨水-SNCR以及尿素-SNCR的影响。结果表明,添加少量的Na₂CO₃可以明显提高低温区域的脱硝效率,同时使NH₃泄漏曲线明显往低温方向偏移,尿素-SNCR过程尾部HNCO泄漏明显降低;添加少量的Na₂CO₃可以明显降低N₂O排放,这在尿素-SNCR过程中尤为明显;Na₂CO₃的添加明显提高了尿素热解气中HNCO向NH₃的转化率,这是尿素-SNCR过程中HNCO泄漏可以显著降低,N₂O排放得以大量减少的主要原因;Na₂CO₃添加量相同时,较低氨氮比工况的脱硝效率促进作用相对更为明显,较高氨氮比工况脱硝温度窗口宽度的扩展作用相对更为有效,而较低氧含量工况的脱硝效率促进效果也相对更为显著。     

诱导期测定法对碳酸锂成核动力学的研究

在288.15～323.15 K温度范围内,采用诱导期测定法研究了碳酸锂(Li₂CO₃)在有无添加NaCl的Li Cl-Na₂CO₃过饱和溶液中的成核动力学.通过OLI电解质与水化学物性分析软件内嵌的全组分模型严格计算Li₂CO₃在溶液中的过饱和度,研究了温度、过饱和度和Na Cl的添加量对Li₂CO₃成核诱导期的影响,并结合经典初级成核理论计算了活化能、固-液界面张力和接触角等成核动力学参数.结果显示,在相同的过饱和度下,Na Cl的添加使得Li₂CO₃的成核诱导期增长;添加Na Cl后Li₂CO₃成核反应的活化能从63.69 k J/mol(溶液中Cl^?的超额含量Y=0)增加到72.85 k J/mol(溶液中Cl^?的超额含量Y=0.5),表明Na Cl的添加抑制了Li_...     

高碱煤含钠矿物沉积层的高温熔融及多相反应过程分析

采用纯矿物试剂模拟燃用高碱煤时炉内受热面典型的灰沉积层化学组成,利用热机械分析（TMA）、TG-DSC分析、高温煅烧实验结合XRD、SEM-EDS表征方法研究了不同Na₂SO₄含量灰沉积层的高温熔融过程及矿物间的多相反应机理。结果表明,掺混Na₂SO₄后沉积层熔化特征温度显著降低,Na₂SO₄的主要反应途径与掺混比例有关,当掺混比低于20%时,Na₂SO₄与SiO₂、CaO、Al₂O₃反应主要转变为CaSO₄和钠的硅铝酸盐;掺混比大于40%时则主要与CaSO₄生成低熔点的钠钙复合硫酸盐。富Na₂SO₄沉积层颗粒在800℃时开始黏结;900-950℃时,霞石、钠长石等钠的硅铝酸盐发生低温共熔,同时Na₂SO₄和CaSO₄生成的复合硫酸盐开始熔融,逐渐形成液相;1200-1250℃时,镁黄长石与含钙矿物发生强烈共熔,温度超过1300℃后矿物完全熔融成为自由液相。     

Recent advances in solving Li2CO3 problems in garnet-based solid-state battery: A systematic review(2020–2023)

Garnet solid electrolytes are one of the most promising electrolytes for solid-state batteries.However,Li₂CO₃ is a critical issue that hinders the practical application of garnet-based solid-state lithium-ion batteries.There are two sources of Li₂CO₃ contamination.The main one is the aging of garnet electrolytes in the atmosphere.Garnet electrolytes can react with H₂O and CO₂ in the air to form Li₂CO₃,which r...     

多级孔ZSM-5分子筛的制备及催化噻吩烷基化性能研究

用不同浓度的Na₂CO₃溶液处理ZSM-5分子筛,采用XRD、XRF、SEM、N₂吸附脱附及NH₃-TPD方法对处理前后的ZSM-5分子筛进行表征,并考察了Na₂CO₃溶液处理对ZSM-5分子筛孔结构、酸性以及噻吩烷基化性能的影响。结果表明,Na₂CO₃溶液处理在保持ZSM-5分子筛微孔骨架结构的同时,增加了ZSM-5分子筛的比表面积、外表面积和介孔体积,并调变了酸性。Na₂CO₃溶液处理提高了ZSM-5分子筛催化剂的噻吩烷基化活性和噻吩选择性。一定反应条件下,随着Na₂CO₃溶液浓度增加,多级孔ZSM-5分子筛的噻吩烷基化性能逐渐提高,而噻吩选择性先增加后下降。当Na₂CO₃溶液浓度为2 mol/L时,分子筛的噻吩转化率和噻吩选择性分别为81.26 %和73.15%。当Na₂CO₃溶液浓度为3 mol/L时,噻吩转化率和选择性分别为90.57 %和72.59%。     

基于实验和密度泛函理论的NaHCO3吸附SeO2机理研究

本研究通过吸附实验探究了140-220℃下NaHCO₃对SeO₂的吸附性能,通过一系列表征解析了吸附后样品中硒的总量、价态和形态,结合密度泛函理论计算,探讨了NaHCO₃对SeO₂的吸附机理。结果表明,NaHCO₃对SeO₂的吸附性能随温度的升高而增加,在吸附过程中同时发生NaHCO₃向Na₂CO₃的分解反应,分解后产生的Na₂CO₃吸附活性更强。SeO₂吸附过程属于SeO₂中Se原子与Na₂CO₃表面O原子成键的化学吸附,吸附产物以亚硒酸盐为主。     

Li2SO4-MgSO4及LiNO3-Mg(NO3)2熔盐体系的研究

用目测变温法和差热分析法研究了Li₂SO₄-MgSO₄、LiNO₃-Mg(NO₃)₂熔盐体系。在前一体系中有固液异组成化合物Li₂SO₄·2MgSO₄生成,它在832°熔化分解。化合物与Li₂SO₄间形成低共熔点,温度为647℃,组成含MgSO₄23.6Wt%。Li₂SO₄多晶转变点575℃,在加入MgSO₄后形成类低共熔点,温度552℃,组成含MgSO₄4.2%。LiNO₃-Mg(NO₃)₂为一简单低共熔体系,共晶点含Mg(NO₃)₂47.3%,温度200℃。     

利用数字化实验探究乙酸乙酯分别与碳酸钠和氢氧化钠相互作用的差异

乙酸乙酯的制备与性质是中学化学的重要实验活动。乙酸乙酯在碱性条件下容易发生水解,但制备时却用碱性的Na₂CO₃溶液收集,这很容易引起学生的困惑。基于Arduino平台设计数字化实验,利用多传感器同步检测,从多角度定量比较乙酸乙酯分别与Na₂CO₃和NaOH溶液反应的差异,并探讨温度、浓度和搅拌对反应的影响,旨在帮助师生深度理解乙酸乙酯与Na₂CO₃和NaOH相互作用的差异。研究发现,虽然在化学热力学上自发,但乙酸乙酯在常温和搅拌条件下与饱和Na₂CO₃溶液几乎不发生反应,在非饱和Na₂CO₃溶液或较高温度下则可发生,而不管在何种条件下与NaOH溶液均能发生强烈作用。由此,基于数字化实验,为常温下饱和Na₂CO₃溶液可用来收集乙酸乙酯提供了充分的证据和理由。     

煤矸石催化气化耦合气化灰提铝过程中K2CO3和Na2CO3作用的对比研究

以煤矸石为研究对象，对比研究了Na₂CO₃与K₂CO₃对煤矸石催化气化反应性及催化气化灰中Al的溶出行为的影响。同时，采用X射线衍射分析（XRD）和热重分析（TGA）研究了不同催化剂及温度作用下矸石中矿物质的热转变过程。结果表明，与K₂CO₃相比，煤矸石中的高岭石更容易与Na₂CO₃反应生成钠霞石，而酸浸可实现钠霞石中铝和硅元素的有效分离。此外，Na₂CO₃作为催化剂时，所得气化灰经盐酸浸取后铝的浸出率可达到94.2%。而K₂CO₃作催化剂时，其铝的浸出率只有83.7%。因此，对矸石催化气化耦合气化灰的铝提取来说，Na₂CO₃催化剂具有更好的选择性。     

Furyl- and thienyl-silatranes and germatranes

We review our research on the synthesis and study of the physical and biological properties of furyl- and thienylgermatranes and -silatranes.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 6, pp. 725–732, June, 1992.     

Review and patents and literature

The use of the insect cell/baculovirus expression system for producing recombinant proteins of bacterial, plant, insect, and mammalian origin has become widespread. The popularity of this eukaryotic expression system is due to many factors, including (1) potentially high protein expression levels, (2) ease and speed of genetic engineering, (3) ability to accommodate large DNA inserts, (4) protein processing similar to higher eukaryotic cells (e.g., mammalian cells), and (5) ease of insect cell growth (e.g., suspension growth). The following review of the literature discusses two engineering aspects of recombinant protein synthesis by insect cell cultures: bioreactor scale-up and insect cell line selection. Following this review patent abstracts and additional literature pertaining to expression of recombinant proteins in insect cell culture are listed.     

多环芳二酐型聚酯亚胺膜的透气性能

多环芳二酐型聚酯亚胺膜的透气性能李悦生，丁孟贤，徐纪平（浙江大学高分子科学与工程研究所，杭州，３１００２７）（中国科学院长春应用化学研究所）关键词聚醚酰亚胺，聚酯酰亚胺，膜，透气性通常的聚酰亚胺加工性能较差，在芳环二酐的苯环间引入醚键等柔性基团后，其...     

微量元素与疾病诊断治疗的研究现状及展望

对国内外微量元素与疾病的关系及其诊断治疗的研究现状及研究动向进行了综述，包括：微量元素与地方病、癌肿、心血管病、糖尿病、眼病、神经系统病等。参考文献72篇。     

Preparation and photolysis of poly-p-ethylacrylophenone and poly-p-chloroacrylophenone and their copolymers with styrene and methyl methacrylate

Poly-p-ethylacrylophenone (PPEtAP) and poly-p-chloroacrylophenone (PPClAP) and their copolymers with styrene (PEtAP/S) and (PClAP/S) and with methyl methacrylate (PEtAP/MMA) and (PClAP/MMA) were prepared. Quantum yields of main-chain scissions at 366 nm at room temperature in benzene solution are of the same order as those of the unsubstituted polyacrylophenone and its copolymers. Substitution with chlorine and ethyl group in the para position compared to the unsubstituted polyacrylophenone and its copolymers leads to an increase of the lifetime for the n–π^* excited triplet state, as is evident from the measured quenching constants of photolysis. The low-temperature emission spectra of the copolymers are similar to the spectra of the model compounds in a polymer film. For the homopolymer, however, the character of the emission spectrum changes considerably.     

Concentrations and distributions of trace and minor elements in Chinese and Canadian coals and ashes

A total of 35 trace and minor elements including some of environmental significance were determined in each of a selection of 15 Chinese and 6 Canadian thermal coals and their ashes by using the SLOWPOKE-2 nuclear reactor facility of the University of Toronto. The concentrations and distributions of these constituents among the coals and their combustion products (viz. ash and volatile matter) are presented together with an interpretation of their significance in relation to the large scale combustion of these coals as thermal fuels in industrialized countries such as China and Canada. The detailed results showed wide variations in trace impurity concentrations (up to a factor of 100 and more) among the coals studied with few large differences between those of Chinese and Canadian origin except that the rare earths, Sc, Th, U, I, and Se were much higher in the former, other halogens, As and Na were lower. Values for elemental enrichment factors (EF) relative to normal crustal abundances indicated that only As(EF=13), Br(5.7), I(16), S(230), Sb(11) and Se(320) were appreciably enriched in coal. During static ashing at 750°C most of the halogens, S and Se were volatilized whereas most other inorganic constituents were highly retained and concentrated in the ash by factors of 6 to 11.