A New Type of Dibenzoyl Tartaric Acid Selective Electrode Baded on Polymer Membrane Containing Calix[4] arene lonophore

A new type of dibenzoyl tartaric acid selective electrode has been developed. Three double-arm calix [4] arene derivatives were employed as the neutral ionophores. The poly(vinyl chloride) membrane electrode containing an amide derivative of calix [4] arene as the neutral carrier and a dibutyl phthalate as the plasticizer exhibited the highest sensitivity for dibenzoyl tartaric acid. The slope of linear portion was 27.8mV per concertration decade. The electrode has a fast response and a long lifetime.     

Synthesis of Calix[4] arene Thia Derivative and Extraction Effect of Substituents on Mercury( Ⅱ) and Lead( Ⅱ)

Calix[4]arene derivatives have been reported to possess high selectivity for metal ions.In order to analyze the extraction effect of substituents on Hg~(2+)and Pb~(2+),calix[4]arene derivatives containing hydroxyl,bromoethoxy and 1,11-dioxa-4,8-dithiahendecene were successfully synthesized,with their extraction effectiveness towards Hg~(2+)and Pb~(2+)were evaluated respectively.The results indicated that the phenolic hydroxyl in calix[4]arene improved the extraction ability on Hg~(2+)by promoting the formation of the negative oxygen ions that could bind with Hg~(2+)by coordination and ionic bonds.The extraction ability of 5,17-dinitro-26,28-(1’,11’-dioxa-4’,8’-dithiahendecene)-calix[4]arene(calix[4]arene thia derivative)was improved slightly due to the better coordination capacity for metal ions after introduction of 1,11-dioxa-4,8-dithiahendecene,which was a chelate-binding centre.Regarding to Pb~(2+),only 1,11-dioxa-4,8-dithiahendecene on molecule contributed to extraction due to the coordination bond.Since the metal ion with higher charge-to-radius ratio could coordinate with one ligand more stably,Pb~(2+)with higher charge-to-radius ratio than Hg~(2+)was coordinated and extracted by the calix[4]arene thia derivative more easily.Furthermore,extraction rates of the calix[4]arene thia derivative on both ions(Hg~(2+)and Pb~(2+))increased with the increase of pH value in acidic aqueous system(pH7).     

Synthesis and Characterization of New Polyimide Containing Calix[4]arenes in the Polymer Backbone with Transport Ability

New polyimide containing calix [4] arene moieties on the polymer backbone was successfully synthesized in N- methy1 - 2 - pyrrolidone （NMP） by polycondensations of 3, 3＇, 4, 4＇- oxydiphthalic anhydride （ODPA） with the diaminocalix[4]arene monomer using 3,3＇- dimethy1- 4, 4＇- The polyimide prepared is soluble in common solvents, such as NMP, DMAc, DMF and chloroform. The polyimide films obtained have excellent thermal stability and mechanical property. At the same time, the liquid membrane transport of potassium ions by the new polyimide was investigated, which testified that compared to ODPA-DADPM polyimide, the polyimide containing culix[4] arenes has the transport ability to metal ions in regard to bulky, cone-like calix [-4] arene moieties.     

Discussion on the mechanism of the calcium absorption in the human body

The present article discusses a new mechanism of calcium absorption in the human body. The mechanism is revealed as follows. First, after food is digested in the stomach, calcium ions (Ca2+) are released. The small intestine secretes amino acid or short peptide chain with small molecular weight automatically, which are called chelating agent; when the calcium ions from the stomach get to the small intestine, the reaction of the chelating agent with the calcium ions occurs, producing the neutral amino acid calcium chelate. Then, this kind of calcium chelate with small molecular weight is absorbed as a whole into the tissues of the small intestine. After being absorbed, in the cell the calcium chelate can break down its chelating bond automatically and decompose into the amino acid and calcium ion again. Finally, the calcium ion goes into blood through portal vein and is transferred to the organs and also deposits on the bone. The reason for the body抯 calcium insufficiency, which has no linear relation with the calcium intake amount, is the lack of the amino acid secreted by the small intestine. The main barrier that influences the calcium absorption is anion pollution. The calcium absorptivity of the body has nothing to do with the solubility of the calcium source out of the body. A new kind of calcium supplement agent——glycine calcium chelate——is synthesized, whose molecular weight is 206.06 (containing a molecular water). If the glycine calcium chelate is used to make calcium supplement agent, about 20 mg calcium element (converted from the glycine calcium chelate, the same below, no longer indicated) per day for one person, 50 mg at most, is enough to maintain the positive balance of calcium metabolism.     

Ion transport-related resistive switching in film sandwich structures

Resistive switching memories based on ion transport and related electrochemical reactions have been extensively studied for years. To utilize the resistive switching memories for high-performance information storage applications, a thorough understanding of the key information of ion transport process, including the mobile ion species, the ion transport paths, as well as the electrochemical reaction behaviors of these ions should be provided for material and device optimization. Moreover, ion transport is usually accompanied by processes of microstructure modification, phase transition, and energy band structure variation that lead to further modulation of other physical properties, e.g., magnetism, optical emission/absorbance, etc., in the resistive switching materials. Therefore, novel resistive switching memories that are controlled through additional means of magnetic or optical stimulus, or demonstrate extra functionalities beyond information storage, can be made possible via well-defined ion transportation in various switching materials and devices. In this contribution, the mechanism of ion transport and related resistive switching phenomena in thin film sandwich structures is discussed first, followed by a glanceat the recent progress in the development of high-performance and multifunctional resistive switching memories. A brief perspective of the ion transport-based resistive switching memories is addressed at the end of this review.     

The interdecadal variation of Indonesian Throughflow and its mechanism

The interdecadal variation of the volume and heat transport of Indonesian Throughflow (ITF) and its mechanism are preliminarily studied on the basis of the updated SODA data. It is found that the interdecadal variation of ITF‘s volume transport is mainly concentrated in upper 714 m and that of ITF‘s heat transport is mainly confined to upper 450 m. There is fairly consistent interdecadal variation in the depth-integrated seawater pressure above different depths in the region south of Davao, north of New Guinea and southwest of Australia. The depth-integrated pressure difference between northwest of Australia and south of Java has best correspondence with ITF‘s volume transport on interdecadal time scales. The relation between the wind stress on the Pacific and ITF‘s volume transport on interdecadal time scales is studied based on Island Rule. It is shown that both the wind stress along the zonal lines just south of Australia and the Equator act as the dominant contributors to ITF‘s volume transport, with the latter dominating the phase of ITF‘s interdecadal variation. These results indicate that the atmospheric forcing and oceanic adjustment in the tropical region both contribute significantly to the ITF‘s interdecadal variation.     

Synthesis and self-assembly of two 1,3-alternate thiacalix[4]arenes derivatives bearing amide groups

Two 1,3-alternate thiacalix[4]arene derivatives bearing amide groups, 1,3-alternate p-tert-butylthiacalix[4]arene tetraamide (4), and 1,3-alternate p-H-thiacalix[4]arene tetraamide (6) were prepared, and their crystal structures were determined by single-crystal X-ray diffraction method. The steric hindrances posed by tert-butyl groups play an important part in the synthesis and the self-assembly of the two compounds. Compound 6 was synthesized from the corresponding ester, which was obtained by the reaction of acid chloride with ammonia. In the crystal structure, compound 4 presents a highly symmetric molecular structure, while for compound 6, because of absence of tert-butyl groups, it presents a more flexible molecular structure.     

Bridging of Calixarenes with N, N＇-Bis（Chloroacetyl） Propylenediamine

A new bridging reagent, N, N‘-bis (chloroacetyl) propylenediamine was used to explore the relativeactivity and bridging pattern of p-ten-bury lcalix [4] arene, p-tert-butylcalix [6] arene and butylcalix [8] arene. It wasfound that the bridging reaction is selectively, at least, preferably at 1, 3-position for p-tert-butylcalix [4] arene and p-tert-butylcalix [6] arene, 1,5-position for p-tert-butylcalix [8] arene. Taking the yield of bridged calixarene as a compar-sion standard, the activity decreases with the increasing of the number of phenolic units in calixarene.     

Synthesis,Characteristics and Applications of Fibrous Composites with Immobilized Nanomolecular Layers of Ferrocyanides and Phosphates of Some d-Elements

1 Results The general principle of the synthesis of fibrous inorganic ion-exchanging composites, containing the combination of polymer analogous conversion reactions of the fibres and cycles of ion-molecular layering is advanced. Synthesis of thin nanomolecular layers of the acid Ti(Ⅳ) and Zr(Ⅳ) phosphates on surface of the cotton fibres and Cu(Ⅱ) and Fe(Ⅲ) ferrocyanides-on polyacrylonitrile fibres was performed on the basis of this principle. By the method of X-ray analysis it was stated that the formed pellicular inorganic layers have a crystalline structure. The synthesis of thin layers of Cu(Ⅱ) and Fe(Ⅲ) hexacyanoferrates (Ⅱ) was performed by the method of the chemosorption layering on a matrix which represented the derivatives of polyacrylonitrile fibres containing HO-N=C·-NH2 groups with the degree of substitution of CN-groups about 50%. According to the data from the X-ray studying of the synthesized pellicular hexacyanoferrates, their composition is described by the formulas KxCu(2-x)[Fe(CN)6]·4H2O and KxFe(4-x)[Fe(CN)6]3 (compounds Ⅰand Ⅱ respectively). By the methods of IR-spectroscopy, formation of heteroatomic cycles by polyacrylonitrile derivatives (with participation of strong H-bonds) was shown. They were capable to disintegrate under the effect ofthe ions of d-metals. It is suggested that strong adhesion of the layers withthe matrix is caused by formation of linkage between [Fe(CN)6]4-ions and the ions in chelates' composition through CN-bridges. The equilibrium ion-exchange capacity on the Rubidium, Cesium and Thallium ions linearly depends on the layer's thickness, which is determined by the number of layering cycles (n) and is equal to 1.0 mmol·g-1 when n=8. Theion-exchange property testing of the synthesized compositions on the basis of the acid Ti(Ⅳ) and Zr(Ⅳ) phosphates was carried out by sorption from water solutions of the strontium and caesium-137 ions, on the basis of the Cu(Ⅱ) and Fe(Ⅲ) ferrocyanides-stable and radioactive caesium isotopes. There is a linear dependency of ion-exchange capacity on the amount of the cycles layering in case the acid Ti(Ⅳ)and Zr(Ⅳ) phosphates is observed. Moreover, the equality of the ionite ion-exchange capacity both on ion strontium, and on ion caesium is observed under fourfold cycle layering. S-figurative nature of such dependence was stated for ferrocyanides. It is shown that the process of the ion exchange proceeding in two stages. The full ion-exchange capacity of ionites on the basis of the acid Ti(Ⅳ) and Zr(Ⅳ) phosphates reaches 2.0 mmol-equ/g, but on the basis Cu(Ⅱ) and Fe(Ⅲ) ferrocyanides-1.0 mmol-equ/g. Ion-exchange equilibrium on synthesized ionites is reachedapproximately 30 times faster, than on corresponding powdery crystalline phosphates and ferrocyanides. Conclusion about prospect of the synthesized material usage in ion-exchange technology, including for extraction of radionuclides is made.     

Synthesis of Bis-substituted Calix[ 4 ] arenes and Mechanism of Substituents Effect on K^ ＋ and Hg^2＋ Ions Transports through Liquid Membrane

New callx[4]arene derivatives containing nitro,amino and benzoyl in the upper and lower rims of molecule were successfully synthesized.Their effectiveness towards K + and Hg2 + across bubbling liquid m...     

杯芳烃对Fe~(3 )离子的液膜传输研究

本文用气泡式准乳化液膜法研究了对叔丁基杯芳烃及其衍生物对Fe3 离子的液膜传输作用 ,并对其传输规律、影响因素 (源相及吸收相的酸度 ,金属离子的浓度 ,传输载体类型等 )及传输机理作了初步探讨 .     

新型手性杯[4]芳烃氨基醇衍生物的合成

杯[4]芳烃与1,2-二溴乙烷反应合成1,3-二溴乙氧基杯[4]芳烃衍生物(化合物1),化合物1分别与乙醇胺和S-(+)-4-甲基-2-氨基-1-戊醇反应,较高产率地合成了含氨基醇片段的杯[4]芳烃衍生物(化合物2)和含手性氨基醇片段杯[4]芳烃衍生物(化合物3).新化合物的结构经元素分析、1HNMR和ESI-MS等表征证实,其结构为1,3-二取代模式且为锥式构象.     

杯芳烃改性壳聚糖对钕离子的吸附性能

采用杯[8]、杯[6]、杯[4]芳烃对壳聚糖颗粒进行包覆改性,并对钕离子吸附性能进行了研究.研究发现,杯芳烃主要靠氢键与壳聚糖作用而包覆于壳聚糖表面,杯[6]和杯[8]芳烃包覆壳聚糖对钕离子的吸附量均远高于壳聚糖,而杯[4]芳烃包覆壳聚糖对钕离子的吸附量则较低,但在钕离子的平衡浓度较低时对钕离子的吸附仍高于壳聚糖.同时还研究了杯芳烃包覆壳聚糖的吸附量和pH值的关系.     

A new type of dibenzoyl tartaric acid selective electrode based on polymer membrane containing calix[4]arene ionophore

A new type of dibenzoyl tartaric acid selective electrode has been developed. Three double-arm calix[4]arene derivatives were employed as the neutral ionophores. The poly(vinyl chloride) membrane electrode containing an amide derivative of calix[4]arene as the neutral carrier and a dibutyl phthalate as the plasticizer exhibited the highest sensitivity for dibenzoyl tartaric acid. The slope of linear portion was 27.8 mV per concertration decade. The electrode has a fast response and a long lifetime.     

杯芳烃的配位化学（Ⅸ）：杯芳烃萃取金属的机理

合成了六对叔丁基杯［６］芳烃，八对叔丁基杯［８］芳烃和四甲基羧基氧基四对叔丁基杯［４］芳烃，并以杯芳烃进行萃取金属离子的研究。对杯芳烃萃取金属的三种机理进行了探讨，并测出其萃取平衡常数。     

Synthesis and characterization of new calix[4]arene amino acid ester derivatives and their metal extraction properties

A new type of calix[4]arenes containing amino acid ester derivatives has been synthesized. Their¹H NMR characteristics are discussed. Metal ion extraction experimental has shown that calix[4]arene amino acid esters (2a, 2b) possess good extraction efficiency for transition metal ions (Cu²⁺, Ni²⁺, Zn²⁺) and poor extraction efficiency for alkali metal ions (Na⁺, K⁺). Foundation item: Supported by the Ziqang Science Foundation of Wuhan University Biography: MENG Ling-zhi(1947-), female, Associate professor.     

Inclusion property and molecular modeling of calix[4]arene derivatives

The inclusion properties of two calix[4]arene derivatives 5, 11, 17, 23-tetra-tert-butyl-25, 27-bis (isopropyl carbamoyl-methoxy)-26,28-diundecenyloxy calix[4]arene (C[4]A) and 25, 27-dibutoxy-5, 11, 17,23-tetra-tert-butyl-26,28-diundecenyloxy calix[4]arene (C[4]B) were studied by gas chromatographic method. It was found that C[4]A could form inclusion complexes with benzene, toluene, methanol and ethanol while C[4]B could only form inclusion complex with methanol, which might be due to the different conformations of C[4]A and C[4]B. Molecular modeling showed that CH/π and OH/π interactions played important roles in the forming of inclusion complexes. Biography: YU Xiao-dong (1973-), male, PhD candidate.     

Synthesis of a new type tetraamides bridged calix[4]arene

Two new tetraamides bridged calix[4]arenes were synthesized by the condensation reaction of 1,3-bis-chlorocarbonylmethyl p-tert-butylcalix[4]arene with 1,2-bis (2′-amino-2′-methylpropanamido) benzene or 1,2-bis (2′-amino-2′-methylpropanamido)-4,5-dichloro benzene, respectively. The new compounds were characterized by¹H-NMR, MS-FAB, and elemental analysis; macrocyclic polyamine. Foundation item: Supported by the National Science Foundation of China (20072029) Biography: Xiao Yuan-jing (1974-), male, Doctor, research direction: supramolecular chemistry.     

杯[4]芳烃固定相分离芳香族位置异构体的热力学特性研究

将双十一碳烯氧基杯[4]芳烃冠醚聚硅氧烷(C[4]C5-PSO)和上缘稀基取代杯[4]芳烃四苄基醚聚硅氧烷(C[4]TBE-PSO)用作毛细管气相色谱固定相,通过测定一些芳香族位置异构体在2种固定相上的热力学参数△H、△S和△G,探讨了杯[4]芳烃衍生物气相色谱固定相对芳香族位置异构体分子识别的特性和保留机理.