Effects of zinc isophthalate on the crystallization and crystal transformation behavior of polybutene alloy

New Hofmann-type metal–organic frameworks display rare and complete ligand exchange induced single crystal to single crystal transformations from 3D frameworks to 2D layers, accompanied by magnetic properties transition from two-step SCO behavior to hysteretic SCO behavior.

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Solid-State Conformational Flexibility at Work: Energetic Landscape of a Single Crystal-to-Single Crystal Transformation in a Cyclic Hexapeptoid

Crystal Growth & Design ◽

10.1021/acs.cgd.0c01244 ◽

2021 ◽

Vol 21 (2) ◽

pp. 897-907

Author(s):

Giovanni Pierri ◽

Marta Corno ◽

Eleonora Macedi ◽

Maria Voccia ◽

Consiglia Tedesco

Keyword(s):

Solid State ◽

Single Crystal ◽

Conformational Flexibility ◽

Crystal Transformation

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Interfacial Compatibility on the Crystal Transformation of Isotactic Poly (1-Butene)/Herb Residue Composite

Polymers ◽

10.3390/polym13101654 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1654

Author(s):

Bo Wang ◽

Shuangdan Mao ◽

Fuhua Lin ◽

Mi Zhang ◽

Yuying Zhao ◽

...

Keyword(s):

Beneficial Effect ◽

Crystal Form ◽

Spontaneous Transformation ◽

Water Contact ◽

Crystal Transformation ◽

Transformation Time ◽

Organic Functional Groups ◽

Silane Coupling ◽

Interfacial Compatibility ◽

Thermal Stability Of

Isotactic poly (1-butene) (iPB) has excellent properties which are recognized as a green and energy saving product. However, the most stable and valuable crystal form I had a spontaneous transformation that took as long as seven days to complete. As a special solid waste, the herb residue (HR) is rich in cellulose which has great potential to accelerate the crystal transformation of the iPB. However, the polarity of HR results in the interface compatibility with non-polar iPB. In this study, the HR was modified by silane coupling agent (KH570) to obtain KHR and the iPB/HR composite was prepared. The FTIR spectrum was indicated that the organic functional groups of KH570 successfully graft onto the surface of HR and the water contact angle test was indicated that the hydrophilicity of the KHR was greatly decreased. The complete crystal transformation time is 7 days for iPB, 6 days for iPB+5% HR but only 3 days for iPB+5% KHR. The addition of the HR and KHR improve the thermal stability of the composite and this beneficial effect is more obvious for KHR. After annealing for 5 days, the physical properties value include tensile strength, flexural strength, and HDT of iPB+5% HR reach that of pure iPB after annealing for 7 days, but only 3 days for iPB+5% KHR. The TG analysis and SEM photographs give clear evidence that the beneficial effect of KH570 modified HR on improving the interface compatibility with iPB.

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Identities on poly-Dedekind sums

Advances in Difference Equations ◽

10.1186/s13662-020-03024-x ◽

2020 ◽

Vol 2020 (1) ◽

Cited By ~ 2

Author(s):

Taekyun Kim ◽

Dae San Kim ◽

Hyunseok Lee ◽

Lee-Chae Jang

Keyword(s):

Modular Group ◽

Reciprocity Relation ◽

Dedekind Sums ◽

Transformation Behavior ◽

Dedekind Eta Function ◽

Bernoulli Function ◽

Bernoulli Functions

Abstract Dedekind sums occur in the transformation behavior of the logarithm of the Dedekind eta-function under substitutions from the modular group. In 1892, Dedekind showed a reciprocity relation for the Dedekind sums. Apostol generalized Dedekind sums by replacing the first Bernoulli function appearing in them by any Bernoulli functions and derived a reciprocity relation for the generalized Dedekind sums. In this paper, we consider the poly-Dedekind sums obtained from the Dedekind sums by replacing the first Bernoulli function by any type 2 poly-Bernoulli functions of arbitrary indices and prove a reciprocity relation for the poly-Dedekind sums.

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Retention of a Four-Fold Interpenetrating Cadmium–Organic Framework through a Three-Step Single Crystal Transformation

Inorganic Chemistry ◽

10.1021/acs.inorgchem.1c01105 ◽

2021 ◽

Author(s):

Jia-Qian Li ◽

Si-Wen Ke ◽

Tong Yan ◽

Yu-Yang Li ◽

Yan Zhou ◽

...

Keyword(s):

Single Crystal ◽

Crystal Transformation ◽

Organic Framework

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Crystal-to-Crystal Transformation from K2[Co(C2O4)2(H2O)2]·4H2O to K2[Co(μ-C2O4)(C2O4)]

Magnetochemistry ◽

10.3390/magnetochemistry7060077 ◽

2021 ◽

Vol 7 (6) ◽

pp. 77

Author(s):

Bin Zhang ◽

Yan Zhang ◽

Guangcai Chang ◽

Zheming Wang ◽

Daoben Zhu

Keyword(s):

Hydrogen Bond ◽

Physical Properties ◽

Crystal Structures ◽

Molecular Crystal ◽

Trigonal Prism ◽

Space Group ◽

Cell Parameters ◽

Oxalate Anion ◽

Crystal Transformation ◽

Antiferromagnetic Ordering

Crystal-to-crystal transformation is a path to obtain crystals with different crystal structures and physical properties. K2[Co(C2O4)2(H2O)2]·4H2O (1) is obtained from K2C2O4·2H2O, CoCl2·6H2O in H2O with a yield of 60%. It is crystallized in the triclinic with space group P1 and cell parameters: a = 7.684(1) Å, b = 9.011(1) Å, c = 10.874(1) Å, α = 72.151(2)°, β = 70.278(2)°, γ = 80.430(2)°, V = 670.0(1) Å3, Z = 2 at 100 K. 1 is composed of K+, mononuclear anion [Co(C2O4)2(H2O)22−] and H2O. Co2+ is coordinated by two bidentated oxalate anion and two H2O in an octahedron environment. There is a hydrogen bond between mononuclear anion [Co(C2O4)2(H2O)22−] and H2O. K2[Co(μ-C2O4)(C2O4)] (2) is obtained from 1 by dehydration. The cell parameters of 2 are a = 8.460(5) Å, b = 6.906 (4) Å, c = 14.657(8) Å, β = 93.11(1)°, V = 855.0(8) Å3 at 100 K, with space group in P2/c. It is composed of K+ and zigzag [Co(μ-C2O4)(C2O42−]n chain. Co2+ is coordinated by two bisbendentate oxalate and one bidentated oxalate anion in trigonal-prism. 1 is an antiferromagnetic molecular crystal. The antiferromagnetic ordering at 8.2 K is observed in 2.

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A Comparative Study of Acicular Ferrite Transformation Behavior between Surface and Interior in a Low C–Mn Steel by HT-LSCM

Metals ◽

10.3390/met11050699 ◽

2021 ◽

Vol 11 (5) ◽

pp. 699

Author(s):

Xiaojin Liu ◽

Guo Yuan ◽

Raja. Devesh Kumar Misra ◽

Guodong Wang

Keyword(s):

Grain Boundaries ◽

Cooling Rate ◽

Acicular Ferrite ◽

Laser Scanning ◽

Sample Surface ◽

Surface Microstructure ◽

In Situ Observation ◽

Low Carbon ◽

Transformation Behavior ◽

Ferrite Transformation

In this study, the acicular ferrite transformation behavior of a Ti–Ca deoxidized low carbon steel was studied using a high-temperature laser scanning confocal microscopy (HT-LSCM). The in situ observation of the transformation behavior on the sample surface with different cooling rates was achieved by HT-LSCM. The microstructure between the surface and interior of the HT-LSCM sample was compared. The results showed that Ti–Ca oxide particles were effective sites for acicular ferrite (AF) nucleation. The start transformation temperature at grain boundaries and intragranular particles decreased with an increase in cooling rate, but the AF nucleation rate increased and the surface microstructure was more interlocked. The sample surface microstructure obtained at 3 °C/s was dominated by ferrite side plates, while the ferrite nucleating sites transferred from grain boundaries to intragranular particles when the cooling rate was 15 °C/s. Moreover, it was interesting that the microstructure and microhardness of the sample surface and interior were different. The AF dominating microstructure, obtained in the sample interior, was much finer than the sample surface, and the microhardness of the sample surface was much lower than the sample interior. The combined factors led to a coarse size of AF on the sample surface. AF formed at a higher temperature resulted in the coarse size. The available particles for AF nucleation on the sample surface were quite limited, such that hard impingement between AF plates was much weaker than that in the sample interior. In addition, the transformation stress in austenite on the sample surface could be largely released, which contributed to a coarser AF plate size. The coarse grain size, low dislocation concentration and low carbon content led to lower hardness on the sample surface.

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