Hydroxyapatite (HA)-zirconium (ZrO2) composite coating was produced by magnetic sputtering on Ti6Al4V titanium alloy substrate, the coatings of 50HA-50ZrO2 and 75HA-25ZrO2 (mass fraction, %) were characterized b...Hydroxyapatite (HA)-zirconium (ZrO2) composite coating was produced by magnetic sputtering on Ti6Al4V titanium alloy substrate, the coatings of 50HA-50ZrO2 and 75HA-25ZrO2 (mass fraction, %) were characterized by scanning electron microscopy, energy disperse spectroscopy, X-ray diffraction and scratch test, respectively, and the effects of HA contents in the coating on residual stress were analyzed. The experimental results show that the phases of HA-ZrO2 composite coatings are HA, ZrO2 and Y2O3, and the HA has a certain decomposition in the combination process, producing TCP and CaO impurity phases. The porous surface of coating is conducive to the growth of bone tissue, and the surface roughness values of 50HA-50ZrO2 and 75HA-25ZrO2 are 1.61 μm and 2.92 μm, respectively. The coating interface is of mechanical integration, the bonding strength values of 50HA-50ZrO2 and 75HA-25ZrO2 are 30 N and 17.5 N, respectively, showing a downward trend with the HA contents increasing. The residual stress values in the coating of 50HA-50ZrO2 and 75HA-25ZrO2 are (-399.1±3.0) MPa, (-343.2±20.3) MPa, respectively, as a result, the appropriate increase of HA contents in the coating will reduce its residual stress.展开更多
To design an effective and realistically applicable sinter bonding process for power devices,we proposed a two-step process using a 200 nm Cu-particle-based paste to form a bondline having high-temperature sustainabil...To design an effective and realistically applicable sinter bonding process for power devices,we proposed a two-step process using a 200 nm Cu-particle-based paste to form a bondline having high-temperature sustainability and superior thermal conductance.This process involved rapid pressure-assisted sinter bonding in air followed by pressureless annealing in a nitrogen atmosphere.In the case of a paste prepared with a mixture of 20 wt.%malic acid and 80 wt.%ethylene glycol,sinter bonding at 300℃and 5 MPa for only 30 s resulted in a sufficient shear strength of 23.1 MPa.The shear strength was significantly enhanced to 69.6 MPa by the additional pressureless aging for 30 min.Therefore,the two-step sinter bonding process is expected to provide an outstanding production rate as a next-generation sinter bonding process.展开更多
C_(10)H_8N_2O_2S_2, Mr=252. 32,monoclinic,P2_(1/c),a=7.165(5).b=7.659(3),c=19.543(8)A,β=96. 76(5)°,V=1065.0(9) A,Z=4,D_c=1. 57 g/cm ̄3.The structure was solved by direct methods and refined to final R(R_w)=0.051...C_(10)H_8N_2O_2S_2, Mr=252. 32,monoclinic,P2_(1/c),a=7.165(5).b=7.659(3),c=19.543(8)A,β=96. 76(5)°,V=1065.0(9) A,Z=4,D_c=1. 57 g/cm ̄3.The structure was solved by direct methods and refined to final R(R_w)=0.051(0.057) for 1446 observed reflections with I≥3σ(Ⅰ).The sulfur-sulfur bond length is found to be 2. 019(2) A with a dihedral angle CSSC of 93.29°.展开更多
The title compound N-[1-(4-chlorophenyl)-1,4-dihydro-4-oxe-6-methylpyridazine- 3-carbonyl]-N(-benzoylhydrazine was prepared by the reaction of 1-(4-chlorophenyl)-1,4- dihydro-4-oxe-6-methylpyridazine-3-carboxylic acid...The title compound N-[1-(4-chlorophenyl)-1,4-dihydro-4-oxe-6-methylpyridazine- 3-carbonyl]-N(-benzoylhydrazine was prepared by the reaction of 1-(4-chlorophenyl)-1,4- dihydro-4-oxe-6-methylpyridazine-3-carboxylic acid with chloroformate ethyl ester and benzoyl hydrazine in the presence of triethylamine. The crystal structure ([C19H15ClN4O3]2·C2H5OH, Mr =811.67) has been determined by X-ray crystal structural analysis. The crystal is monoclinic, space group P21/c, with unit cell parameters a=13.296(3), b=17.155(3), c=17.459(3)?,β=98.959(4), Z=4, V=3934(1) ?3, Dc=1.371g/cm3, F(000)=1688, μ(MoKα)=0.226 mm-1, R=0.0495, wR=0.1348 for 3345 observed reflections (I >2σ(I)). The hydrogen bonds N(3)-H…O(1) , N(7)-H…O(4), and N(8)-H…O(2) can be observed.展开更多
Crystal structure of copper(Ⅱ) complex with a new mesocyclic diamine ligand 3-hydroxyl-1, 5-diazacyclooctane, Cu [C_(12)H_(28)N_4O_2]Br_2, M_r= 483. 7 is reported. It crystallizes in orthorhombic Pbca with a= 16. 201...Crystal structure of copper(Ⅱ) complex with a new mesocyclic diamine ligand 3-hydroxyl-1, 5-diazacyclooctane, Cu [C_(12)H_(28)N_4O_2]Br_2, M_r= 483. 7 is reported. It crystallizes in orthorhombic Pbca with a= 16. 201 (5), b=10. 513 (4), c=9. 992(4) A, V=1701. 8(7) A ̄3, Z=4, D_c=1. 888 g/cm ̄3, μ=49. 5 cm ̄(-1) (MoKa),F(000) = 972. The final R and Rto are 0. 039 and 0. 047 for 1052 observed reflections with I≥3σ(I). The result of X-ray structure determination shows that 3hydroxyl-1,5-diazacyclooctane forms a 2 :1 complex with CuBr_2 in which the central copper ion is sandwiched between the two ligands.展开更多
Imidazole base was crystallized with different aromatic carboxylic acids 2,4-dihydroxybenzoic acid, 5-chlorosalicylic acid, and 1,8-naphthalic acid, affording three new binary molecular organic salts of [(C 3 H 5 N 2 ...Imidazole base was crystallized with different aromatic carboxylic acids 2,4-dihydroxybenzoic acid, 5-chlorosalicylic acid, and 1,8-naphthalic acid, affording three new binary molecular organic salts of [(C 3 H 5 N 2 + )·(C 7 H 5 O 4 )] (1), [(C 3 H 5 N 2 + )·(C 7 H 4 O 3 Cl )] C 7 H 5 O 3 Cl (2), and [(C 3 H 5 N 2 + ) (C 12 H 7 O 4 )] (3). Proton transfer occurs from the COOH of carboxylic acid to nitrogen of imidazole in all complexes (1-3), leading to the hydrogen bond N-H…O in all structures. To our knowledge, the recognition pattern between the carboxylic acid group and imidazole (acid-imidazole synthon) is less well-studied so far. The cooperation among COOH, COO and imidazolium cation functional groups for the observed hydrogen bond synthons is examined in the three structures. Generally, the strong N-H…O and O-H…O hydrogen bonds define supramolecular architecture and connectivity within chains, while weaker C-H…O hydrogen bonds play the dominant role in controlling the interactions between layers in these novel organic salts. Thermal stability of these compounds has been investigated by thermogravimetric analysis (TGA) of mass loss.展开更多
The results of crystallographic analyses on 1:1 and 1:4 well-defined co-crystals formed between glycine anhydride and each of 4-hydroxybenzoic acid and 3,5-dihydroxybenzoic acid are described. Neutral molecules are ...The results of crystallographic analyses on 1:1 and 1:4 well-defined co-crystals formed between glycine anhydride and each of 4-hydroxybenzoic acid and 3,5-dihydroxybenzoic acid are described. Neutral molecules are connected via heteromeric O-H.-.O and N-H…O contacts leading to different packing arrangements of supramolecular chains. On the basis of the molec- ular structures of glycine anhydride and carboxylic acid guests, the hydrogen bonds are arranged to give centrosymmetric synthons V and VII which are noteworthy for their robustness. Hydrogen-bond interactions between glycine anhydride and aromatic acid provide sufficient driving force to direct molecular recognition and crystal packing. Utilization of the orientation of functional groups of the building blocks, the acidity, and weak interactions provides a route for the creation of novel supra- molecular architectures in the crystal lattice. Both two co-crystals contain the expected hydrogen-bonded motifs, and there has been no proton transfer from either of the two carboxylic acids to the aza compound moiety. This demonstrates that glycine anhydride is very capable of affecting the construction of binary co-crystals in a predictable and rationale manner. It is noted that synthons Ⅷ and IX are fairly large, but the real challenge in crystal engineering is to find a big enough synthon that occurs often enough. Thermal stability of these compounds has been investigated by thermogravimetric analysis (TGA) of mass loss.展开更多
Four hydroxybenzoic acid building blocks, m-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxyterephthalic acid, and 5-hydroxyisophthalic acid, have been synthesized as robust cocrystallizing agents and emp...Four hydroxybenzoic acid building blocks, m-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxyterephthalic acid, and 5-hydroxyisophthalic acid, have been synthesized as robust cocrystallizing agents and employed in reactions with piperazine, including [(C4H12N2 2+).(C7H5O3-)2] (l), [(CaH12N2 2+).(C7H5O4-)2] (2), [(C4H12N2 2+).(C8H5O6 2- )] (3), and [(C4H12N2 2+)1/2. (C8H5O5)] . 2H2O (4). Hydrogen-bonded directed assemblies of four salts were validated by single-crystal X-ray diffraction analysis. In compounds 1-4, hydroxybenzoic acids are all deprotonated and piperazine molecules are all protonated to form piperazine dications and keep the chair conformation. Thermal stability of these compounds has been investigated.展开更多
Objective: To study the feasibility of regenerating a whole menisci using poly-(3- hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffolds loaded with meniscal cells in rabbits undergoing total meniscectomy, and t...Objective: To study the feasibility of regenerating a whole menisci using poly-(3- hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffolds loaded with meniscal cells in rabbits undergoing total meniscectomy, and to explore its protective effect on carti- lage degeneration. Methods: A solvent casting and particulate leaching technique was employed to fabricate biodegradable PHBV scaffolds into a meniscal shape. The proliferated meniscal cells were seeded onto the polymer scaffolds, transplanted into rabbit knee joints whose lateral menisci had been removed. Eight to 18 weeks after transplantation, the rege- nerated neomenisci were evaluated by gross and histologi- cal observations. Cartilage Mankin score. degeneration was assessed by Results: Eighteen weeks after transplantation, the implants formed neomenisci. Hematoxylin and eosin (HE) staining of the neomenisci sections revealed regeneration of fibrocartilage. Type I collagen in the neomenisci was also proved similar to normal meniscal tissue by immunohis-tochemical analysis and Sirius scarlet trinitrophenol staining. Articular cartilage degeneration was observed 8 weeks af- ter implantation. It was less severe as compared with that in total meniscectomy controls and no further degeneration was observed at 18 weeks. At that time, the regenerated neomenisci strongly resembled normal meniscal fibrocarti- lage in gross and histological appearance, and its mechani- cal property was also close to that of normal meniscus. Conclusions: The present study demonstrates the feasibility of tissue-engineering a whole meniscal structure in total meniscectomy rabbit models using biodegradable PHBV scaffolds together with cultured allogeneic meniscal cells. Cartilage degeneration is decreased. But long-term in vivo investigations on the histological structure and cartilage degeneration of the neomenisci regenerated by this method are still necessary to determine the clinical potential of this tissue engineering avenue.展开更多
Complexation of the planar multidentate ligand 3,5-bis-(2-hydroxyphenyl)pyrazole (H3L) with manganese chloride leads to the formation of the polynuclear complex [MnIHsL4Oa(MeO)a(MeOH)8] (1). 1 has an octanuc...Complexation of the planar multidentate ligand 3,5-bis-(2-hydroxyphenyl)pyrazole (H3L) with manganese chloride leads to the formation of the polynuclear complex [MnIHsL4Oa(MeO)a(MeOH)8] (1). 1 has an octanuclear macrocyclic core in which the MnnI ions are bridged by four L molecules to form a ring type structure. Antiferromagnetic interactions were shown to be op- erative between metal centers.展开更多
基金Project (08KJB430002) supported by the Natural Science Foundation of the Higher Education Institutions of Jiangsu Province, ChinaProject (CJ20110019) supported by the Applied Basic Research Programs of Changzhou City, China
文摘Hydroxyapatite (HA)-zirconium (ZrO2) composite coating was produced by magnetic sputtering on Ti6Al4V titanium alloy substrate, the coatings of 50HA-50ZrO2 and 75HA-25ZrO2 (mass fraction, %) were characterized by scanning electron microscopy, energy disperse spectroscopy, X-ray diffraction and scratch test, respectively, and the effects of HA contents in the coating on residual stress were analyzed. The experimental results show that the phases of HA-ZrO2 composite coatings are HA, ZrO2 and Y2O3, and the HA has a certain decomposition in the combination process, producing TCP and CaO impurity phases. The porous surface of coating is conducive to the growth of bone tissue, and the surface roughness values of 50HA-50ZrO2 and 75HA-25ZrO2 are 1.61 μm and 2.92 μm, respectively. The coating interface is of mechanical integration, the bonding strength values of 50HA-50ZrO2 and 75HA-25ZrO2 are 30 N and 17.5 N, respectively, showing a downward trend with the HA contents increasing. The residual stress values in the coating of 50HA-50ZrO2 and 75HA-25ZrO2 are (-399.1±3.0) MPa, (-343.2±20.3) MPa, respectively, as a result, the appropriate increase of HA contents in the coating will reduce its residual stress.
基金the Materials&Components Technology Development Program(10080187)the Ministry of Trade,Industry&Energy(MI,Korea).
文摘To design an effective and realistically applicable sinter bonding process for power devices,we proposed a two-step process using a 200 nm Cu-particle-based paste to form a bondline having high-temperature sustainability and superior thermal conductance.This process involved rapid pressure-assisted sinter bonding in air followed by pressureless annealing in a nitrogen atmosphere.In the case of a paste prepared with a mixture of 20 wt.%malic acid and 80 wt.%ethylene glycol,sinter bonding at 300℃and 5 MPa for only 30 s resulted in a sufficient shear strength of 23.1 MPa.The shear strength was significantly enhanced to 69.6 MPa by the additional pressureless aging for 30 min.Therefore,the two-step sinter bonding process is expected to provide an outstanding production rate as a next-generation sinter bonding process.
文摘C_(10)H_8N_2O_2S_2, Mr=252. 32,monoclinic,P2_(1/c),a=7.165(5).b=7.659(3),c=19.543(8)A,β=96. 76(5)°,V=1065.0(9) A,Z=4,D_c=1. 57 g/cm ̄3.The structure was solved by direct methods and refined to final R(R_w)=0.051(0.057) for 1446 observed reflections with I≥3σ(Ⅰ).The sulfur-sulfur bond length is found to be 2. 019(2) A with a dihedral angle CSSC of 93.29°.
基金the National Nature Science Foundation (29832050).
文摘The title compound N-[1-(4-chlorophenyl)-1,4-dihydro-4-oxe-6-methylpyridazine- 3-carbonyl]-N(-benzoylhydrazine was prepared by the reaction of 1-(4-chlorophenyl)-1,4- dihydro-4-oxe-6-methylpyridazine-3-carboxylic acid with chloroformate ethyl ester and benzoyl hydrazine in the presence of triethylamine. The crystal structure ([C19H15ClN4O3]2·C2H5OH, Mr =811.67) has been determined by X-ray crystal structural analysis. The crystal is monoclinic, space group P21/c, with unit cell parameters a=13.296(3), b=17.155(3), c=17.459(3)?,β=98.959(4), Z=4, V=3934(1) ?3, Dc=1.371g/cm3, F(000)=1688, μ(MoKα)=0.226 mm-1, R=0.0495, wR=0.1348 for 3345 observed reflections (I >2σ(I)). The hydrogen bonds N(3)-H…O(1) , N(7)-H…O(4), and N(8)-H…O(2) can be observed.
文摘Crystal structure of copper(Ⅱ) complex with a new mesocyclic diamine ligand 3-hydroxyl-1, 5-diazacyclooctane, Cu [C_(12)H_(28)N_4O_2]Br_2, M_r= 483. 7 is reported. It crystallizes in orthorhombic Pbca with a= 16. 201 (5), b=10. 513 (4), c=9. 992(4) A, V=1701. 8(7) A ̄3, Z=4, D_c=1. 888 g/cm ̄3, μ=49. 5 cm ̄(-1) (MoKa),F(000) = 972. The final R and Rto are 0. 039 and 0. 047 for 1052 observed reflections with I≥3σ(I). The result of X-ray structure determination shows that 3hydroxyl-1,5-diazacyclooctane forms a 2 :1 complex with CuBr_2 in which the central copper ion is sandwiched between the two ligands.
基金supported by the National Natural Science Foundation of China (20701023, 20971076)the Natural Science Foundation of Shandong Province, China (BS2010NJ004,2009ZRB019KH)
文摘Imidazole base was crystallized with different aromatic carboxylic acids 2,4-dihydroxybenzoic acid, 5-chlorosalicylic acid, and 1,8-naphthalic acid, affording three new binary molecular organic salts of [(C 3 H 5 N 2 + )·(C 7 H 5 O 4 )] (1), [(C 3 H 5 N 2 + )·(C 7 H 4 O 3 Cl )] C 7 H 5 O 3 Cl (2), and [(C 3 H 5 N 2 + ) (C 12 H 7 O 4 )] (3). Proton transfer occurs from the COOH of carboxylic acid to nitrogen of imidazole in all complexes (1-3), leading to the hydrogen bond N-H…O in all structures. To our knowledge, the recognition pattern between the carboxylic acid group and imidazole (acid-imidazole synthon) is less well-studied so far. The cooperation among COOH, COO and imidazolium cation functional groups for the observed hydrogen bond synthons is examined in the three structures. Generally, the strong N-H…O and O-H…O hydrogen bonds define supramolecular architecture and connectivity within chains, while weaker C-H…O hydrogen bonds play the dominant role in controlling the interactions between layers in these novel organic salts. Thermal stability of these compounds has been investigated by thermogravimetric analysis (TGA) of mass loss.
基金financially supported by the National Natural Science Foundation of China (20701023, 51102138)the Natural Science Foundation of Shandong Province, China (BS2010NJ004,2009ZRB019KH)
文摘The results of crystallographic analyses on 1:1 and 1:4 well-defined co-crystals formed between glycine anhydride and each of 4-hydroxybenzoic acid and 3,5-dihydroxybenzoic acid are described. Neutral molecules are connected via heteromeric O-H.-.O and N-H…O contacts leading to different packing arrangements of supramolecular chains. On the basis of the molec- ular structures of glycine anhydride and carboxylic acid guests, the hydrogen bonds are arranged to give centrosymmetric synthons V and VII which are noteworthy for their robustness. Hydrogen-bond interactions between glycine anhydride and aromatic acid provide sufficient driving force to direct molecular recognition and crystal packing. Utilization of the orientation of functional groups of the building blocks, the acidity, and weak interactions provides a route for the creation of novel supra- molecular architectures in the crystal lattice. Both two co-crystals contain the expected hydrogen-bonded motifs, and there has been no proton transfer from either of the two carboxylic acids to the aza compound moiety. This demonstrates that glycine anhydride is very capable of affecting the construction of binary co-crystals in a predictable and rationale manner. It is noted that synthons Ⅷ and IX are fairly large, but the real challenge in crystal engineering is to find a big enough synthon that occurs often enough. Thermal stability of these compounds has been investigated by thermogravimetric analysis (TGA) of mass loss.
基金supported by the National Natural Science Foundation of China (20701023,20971076)the Natural Science Foundation of Shandong Province,China (BS2010NJ004,2009ZRB019KH)
文摘Four hydroxybenzoic acid building blocks, m-hydroxybenzoic acid, 2,4-dihydroxybenzoic acid, 2,5-dihydroxyterephthalic acid, and 5-hydroxyisophthalic acid, have been synthesized as robust cocrystallizing agents and employed in reactions with piperazine, including [(C4H12N2 2+).(C7H5O3-)2] (l), [(CaH12N2 2+).(C7H5O4-)2] (2), [(C4H12N2 2+).(C8H5O6 2- )] (3), and [(C4H12N2 2+)1/2. (C8H5O5)] . 2H2O (4). Hydrogen-bonded directed assemblies of four salts were validated by single-crystal X-ray diffraction analysis. In compounds 1-4, hydroxybenzoic acids are all deprotonated and piperazine molecules are all protonated to form piperazine dications and keep the chair conformation. Thermal stability of these compounds has been investigated.
基金This study was supported by the fundation of Hi-tech Research and Development Program (863 Program) project (2008AA02Z437) and the National Natural Science Foundation of China (No. 30600632).
文摘Objective: To study the feasibility of regenerating a whole menisci using poly-(3- hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) scaffolds loaded with meniscal cells in rabbits undergoing total meniscectomy, and to explore its protective effect on carti- lage degeneration. Methods: A solvent casting and particulate leaching technique was employed to fabricate biodegradable PHBV scaffolds into a meniscal shape. The proliferated meniscal cells were seeded onto the polymer scaffolds, transplanted into rabbit knee joints whose lateral menisci had been removed. Eight to 18 weeks after transplantation, the rege- nerated neomenisci were evaluated by gross and histologi- cal observations. Cartilage Mankin score. degeneration was assessed by Results: Eighteen weeks after transplantation, the implants formed neomenisci. Hematoxylin and eosin (HE) staining of the neomenisci sections revealed regeneration of fibrocartilage. Type I collagen in the neomenisci was also proved similar to normal meniscal tissue by immunohis-tochemical analysis and Sirius scarlet trinitrophenol staining. Articular cartilage degeneration was observed 8 weeks af- ter implantation. It was less severe as compared with that in total meniscectomy controls and no further degeneration was observed at 18 weeks. At that time, the regenerated neomenisci strongly resembled normal meniscal fibrocarti- lage in gross and histological appearance, and its mechani- cal property was also close to that of normal meniscus. Conclusions: The present study demonstrates the feasibility of tissue-engineering a whole meniscal structure in total meniscectomy rabbit models using biodegradable PHBV scaffolds together with cultured allogeneic meniscal cells. Cartilage degeneration is decreased. But long-term in vivo investigations on the histological structure and cartilage degeneration of the neomenisci regenerated by this method are still necessary to determine the clinical potential of this tissue engineering avenue.
基金a Grant-in-Aid for Scientific Research and for Priority Area "Coordination Programming" (area 2107) from MEXT,Japan
文摘Complexation of the planar multidentate ligand 3,5-bis-(2-hydroxyphenyl)pyrazole (H3L) with manganese chloride leads to the formation of the polynuclear complex [MnIHsL4Oa(MeO)a(MeOH)8] (1). 1 has an octanuclear macrocyclic core in which the MnnI ions are bridged by four L molecules to form a ring type structure. Antiferromagnetic interactions were shown to be op- erative between metal centers.