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Osteoinductivity is a crucial factor to determine the success and efficiency of posterolateral spinal fusion (PLF) by employing calcium phosphate (Ca-P) bioceramics. In this study, three kinds of Ca-P ceramics with microscale to nanoscale gain size (BCP-control, BCP-micro and BCP-nano) were prepared and their physicochemical properties were characterized. BCP-nano had the spherical shape and nanoscale gain size, BCP-micro had the spherical shape and microscale gain size, and BCP-control (BAM®) had the irregular shape and microscale gain size. The obtained BCP-nano with specific nanotopography could well regulate in vitro protein adsorption and osteogenic differentiation of MC3T3 cells. In vivo rabbit PLF procedures further confirmed that nanotopography of BCP-nano might be responsible for the stronger bone regenerative ability comparing with BCP-micro and BCP-control. Collectedly, due to nanocrystal similarity with natural bone apatite, BCP-nano has excellent efficacy in guiding bone regeneration of PLF, and holds great potentials to become an alternative to standard bone grafts for future clinical applications., Graphical abstract Image 1, Highlights • The nanocrystal of porous BCP ceramic spheres is similar to natural bone apatite. • BCP nanoceramics is conducive to protein adsorption and osteogenic differentiation of MC3T3 cells. • Osteoindutivity of BCP ceramics is a crucial factor to determine the sucess and efficiency of PLF. • BCP ceramic spheres with nanotopography hold great potential in clinical PLF applications.

Cong Feng, Yonghao Wu, Quanle Cao, Xiangfeng Li, Xiangdong Zhu, Xingdong Zhang National Engineering Research Center for Biomaterials, Sichuan University, Chengdu, Sichuan, People’s Republic of ChinaCorrespondence: Xiangfeng Li; Xiangdong ZhuSichuan University, No. 24 South Section 1, Yihuan Road, Chengdu 610065, People’s Republic of ChinaTel/Fax +86-2885417654Email hkdlxiangfeng@163.com; zhu_xd1973@scu.edu.cnBackground: There is still a big challenge to achieve a balance between mechanical characteristics and biological properties in biphasic calcium phosphate (BCP) ceramics.Purpose: The present study focused on the in-situ whisker growth on BCP ceramics via different hydrothermal treatments and investigated the influences of these whiskers on the mechanical property and biological performance of the ceramics.Methods: Five kinds of BCP ceramics with in-situ whisker growth, ie, BCP-C, BCP-HNO3, BCP-Citric, BCP-NaOH, BCP-CaCl2 and BCP-Na3PO4 were fabricated by different hydrothermal treatments. The phase compositions, morphologies, crystal structures and mechanical strengths of the obtained BCP ceramics were firstly characterized. Then, the in vitro cell adhesion, proliferation and alkaline phosphatase (ALP) activity of bone marrow stromal cells (BMSCs) on the BCP ceramics were evaluated. Lastly, the effects of in-situ whisker growth on the bone-like apatite formation abilities of BCP ceramics were also investigated by immersing them in simulated body fluid (SBF).Results: The results demonstrated that the hydrothermal conditions, especially the hydrothermal media, were crucial to determine the phase composition and morphology of the in-situ whisker. Especially among the five media used (HNO3, Citric, NaOH, CaCl2 and Na3PO4), the Na3PO4 treatment resulted in the shortest whisker with a unique hollow structure, and kept the original biphasic composition. All five kinds of whiskers increased the mechanical strength of BCP ceramics to some extent, and showed the good ability of bone-like apatite formation. The in vitro cell study demonstrated that the in-situ whisker growth had no adverse but even positive effect on the adhesion, proliferation and ALP activity of BMSCs.Conclusion: Due to the growth of in-situ whiskers, the mechanical property and biological performance of the obtained BCP ceramics could increase simultaneously. Therefore, in-situ whiskers growth offers a promising strategy for the expanded application of BCP ceramics to meet the requirements of regenerative medicine.Keywords: in-situ whisker, hydrothermal treatment, biphasic calcium phosphate, mechanical property, bioactivity

Inspired by the nanostructure of bone, biomimetic nanocomposites comprising natural polymers and inorganic nanoparticles have gained much attention for bone regenerative applications. However, the mechanical and biological performances of nanocomposites are largely limited by the inhomogeneous distribution, uncontrolled size and irregular morphology of inorganic nanoparticles at present. In this work, an innovative in situ precipitation method has been developed to construct a biomimetic nanocomposite which consists of spherical hydroxyapatite (HA) nanoparticles and gelatin (Gel). The homogeneous dispersion of HA nanoparticles in nHA–Gel endowed it with a low swelling ratio, enhanced mechanical properties and slow degradation. Moreover, strontium (Sr) was incorporated into HA nanoparticles to further enhance the bioactivity of nanocomposites. In vitro experiments suggested that nHA–Gel and Sr–nHA–Gel facilitated cell spreading and promoted osteogenic differentiation of bone-marrow-derived mesenchymal stem cells (BMSCs) as compared to pure Gel and mHA–Gel conventional composites developed by mechanical mixing. In vivo rat critical-sized calvarial defect repair further confirmed that nHA–Gel and Sr–nHA–Gel possessed relatively effective bone regenerative abilities among the four groups. Collectively, the biomimetic nanocomposites of nHA–Gel and Sr–nHA–Gel have good efficacy in inducing bone regeneration and would be a promising alternative to bone grafts for clinical applications.

Digital light processing (DLP) is one of the additive manufacturing (AM) technologies suitable for preparation of high-performance ceramics. The present study provided an optimized formula to fabricate osteoinductive calcium phosphate (CaP) ceramics with high precision and controllable three-dimensional (3D) structure. Among the four surfactants, monoalcohol ethoxylate phosphate was the best one to modify the CaP powders for preparing the photocurable slurry with high solid loading and good spreading ability. By testing the photopolymerization property of the 60 wt % solid loading slurry, the appropriate processing parameters including the slice thickness (50 μm), exposure intensity (10.14 mW/cm2), and exposure time (8 s) were set to perform the 3D printing of the ceramic green body in the DLP system. After the debinding and sintering, the final CaP ceramics were acquired. The stereomicroscope and SEM observation confirmed the high precision of the ceramics. The average compressive strength of the ceramics with 64.5% porosity reached 9.03 MPa. On only soaking in simulated body fluid for 1 day, an even layer of apatite formed on the ceramic surface. The cell culture confirmed that the ceramics could allow the good attachment, growth, and proliferation of murine bone marrow mesenchymal stem cells. After implantation into the dorsal muscles of beagle dogs for 3 months, abundant blood vessels and obvious ectopic bone formation were observed clearly by the histological evaluation. Therefore, with good bioactivity and osteoinductivity as well as high precision and adjustable mechanical strength, the 3D printed CaP ceramics in the DLP system could have good potential in customized bone-repairing applications.

So far, how to achieve the optimal regenerative repair of large load-bearing bone defects using artificial bone grafts is a huge challenge in clinic. In this study, a strategy of combining osteoinductive biphasic calcium phosphate (BCP) bioceramic scaffolds with intramedullary nail fixation for creating stable osteogenic microenvironment was applied to repair large segmental bone defects (3.0 cm in length) in goat femur model. The material characterization results showed that the BCP scaffold had the initial compressive strength of over 2.0 MPa, and total porosity of 84%. The cell culture experiments demonstrated that the scaffold had the excellent ability to promote the proliferation and osteogenic differentiation of rat bone marrow-derived mesenchymal stem cells (BMSCs). The in vivo results showed that the intramedullary nail fixation maintained the initial stability and structural integrity of the implants at early stage, promoting the osteogenic process both guided and induced by the BCP scaffolds. At 9 months postoperatively, good integration between the implants and host bone was observed, and a large amount of newborn bones formed, accompanying with the degradation of the material. At 18 months postoperatively, almost the complete new bone substitution in the defect area was achieved. The maximum bending strength of the repaired bone defects reached to the 100% of normal femur at 18 months post-surgery. Our results demonstrated the good potential of osteoinductive BCP bioceramics in the regenerative repair of large load-bearing bone defects. The current study could provide an effective method to treat the clinical large segmental bone defects., Graphical abstract Image 1, Highlights • A novel strategy of achieving regenerative repair for large segmental bone defects with osteoinductive calcium phosphate bioceramics was developed successfully. • The critical-sized goat femur defects (3.0 cm in length) were completely repaired by osteoinductive calcium phosphate bioceramics without using exogenous active factors or cells. • The current study could provide an effective method to solve the clinical problem about large load-bearing bone defect repair.

The regeneration of bone defects in osteoporotic patients presents a big challenge. Icariin (Ica), which is the main active component of traditional Chinese medicine - herba epimedii, has been widely loaded to scaffolds for the treatment of bone fracture and osteoporosis. To increase drug loading capacity, and meanwhile achieve a stable and safe drug delivery, in present study, a novel icariin derivative - thiolated icariin (Ica-SH) molecule with good cytocompatibility and bioactivity was incorporated into biphasic calcium phosphate (BCP) ceramic scaffold through Ica-SH intermolecular disulfide bonds (abbr., Ica-SH/BCP) to form film coating. Compared with Ica-loaded BCP scaffolds via physical adsorption (abbr., Ica/BCP), the formation of Ica-SH intermolecular disulfide bonds in Ica-SH/BCP scaffolds led to a decreased real-time drug release concentration, and a reduced drug release rate. The released drug from Ica-SH/BCP scaffolds could promote the proliferation, migration, and osteoblastic differentiation of ovariectomized rat bone mesenchymal stem cells (OVX-rBMSCs), and up-regulate the angiogenic gene expression in human umbilical vein endothelial cells (HUVECs) in vitro. The OVX-rat femoral condyle defect model also demonstrated that Ica-SH/BCP scaffolds promoted a superior bone regeneration in osteoporotic animals than BCP ones. These findings suggest that Ica-SH is a promising drug, which can be facilely incorporated into a variety of scaffolds for repairing bone defects of patients, in particular the ones with osteoporosis.

Further enhance the bioactivity and osteoinductivity of biphasic calcium phosphate (BCP) bioceramics to meet the requirements of regenerative medicine is still a hot topic. Due to the uncontrolled pore structure and large grain size, the osteoinductivity of the conventional BCP bioceramics is restricted to a large extent. Herein, this study introduced a novel pore foaming method to fabricate BCP bioceramics with appropriately ordered macropores and abundant micropores by combing the advantages of the microsphere-sintering method with the H2O2 gas foaming method. Moreover, different sintering methods were adopted to adjust the micro-nano topography of BCP bioceramics. Due to the optimal design of pore size distribution and nano topography, the obtained BCP bioceramics could well trigger and regulate in vitro biological responses, such as degradation, bone-like apatite formation, protein adsorption, cell behaviors, angiogenic and osteogenic differentiation. In vivo canine intramuscular implantation further confirmed that the nanotopography and appropriately ordered pore structure might be responsible for the excellent neovascularization and osteoinductivity of the obtained BCP bioceramics. Collectedly, the osteoinductivity of BCP bioceramics was further enhanced by optimally designing pore structure and micro-nano topography, which hold huge potential to be a potential alternative to the gold standard of autogenous bone in bone repairing applications.

Enhancing the electrode/electrolyte interface stability of high-capacity LiNi0.8Co0.15Al0.05O2 (LNCA) cathode material is urgently required for its application in next-generation lithium-ion battery. Herein, we demonstrate that enhanced interfacial stability of LNCA can be achieved by simply introducing 2 wt % N-allyl-N,N-bis(trimethylsilyl)amine (NNB) electrolyte additive. Electrolyte oxidation reactions and electrode structural destruction are greatly suppressed in the electrolyte with NNB additive, leading to improved cyclic stability of LNCA from 72.8 to 86.2% after 300 cycles. The mechanism of NNB on improving the cyclic stability of LNCA has been verified to its excellent solid electrolyte interface (SEI) film-forming capability. Moreover, the X-ray diffraction and X-ray photoelectron spectroscopy results indicate that the NNB-derived Si-containing SEI film restrains the Li/Ni disorder of LNCA during cycling, which further improves the cyclic stability of Ni-rich LNCA. Importantly, the charging/disc...

It is of significance to further improve the bioactivity of existing calcium phosphate (Ca-P) biomaterials to satisfy the needs of regenerative medicine. Due to its compositional similarity to natural bone mineral, calcium-deficient hydroxyapatite (CDHA) is supposed to possess excellent bioactivity. However, it is difficult to fabricate Ca-P ceramics with a high amount of CDHA, as CDHA is easy to decompose during the sintering process. The present study introduced an effective approach to stabilize CDHA in biphasic calcium phosphate (BCP) ceramics by adding alginate, and investigated the roles of CDHA in their biological performances. The characterization of the phase composition, crystal structure, and functional group demonstrated that the addition of alginate could obviously inhibit CDHA decomposition to attain novel BCP ceramics with a high CDHA content (BCP-A), which could better mimic the inorganic composition of natural bones as compared with the conventional BCP ones (BCP-C). In vitro studies suggested BCP-A showed better bioactivity and osteoinductive capacity than BCP-C, as evidenced by the increased serum protein adsorption, better bone-like apatite formation and cell spreading, and promoted osteogenic differentiation. In vivo intramuscular implantation further confirmed that BCP-A could induce more ectopic bone formation than BCP-C, suggesting BCP-A had a stronger osteoinductivity. Altogether, this study demonstrates that the stabilization of CDHA in BCP ceramics by adding alginate offers a promising principle for designing regenerative biomaterials to process superior biological performances.

Spherical calcium phosphate (Ca-P) granules show advantages in filling bone cavity defects. In this study, gelatinizing technology combined with microsphere-sintering and gas-foaming methods was applied to fabricate porous spherical Ca-P bioceramic granules. The obtained three kinds of Ca-P granules (i.e., hydroxyapatite, HA-G; biphasic calcium phosphate, BCP-G; and tricalcium phosphate, TCP-G) exhibited uniformly spherical shapes and interconnected pore structures with controlled macropores (about 600 μm), and abundant minor- (10-100 μm) to microsized (10 μm) pores. The obtained Ca-P granules contained only the HA and β-TCP phases, but their phase ratios (HA/β-TCP) had some changes in the sintering process. All of the Ca-P granules were favorable for serum protein adsorption and bonelike apatite formation, and TCP-G was superior to the other two. Cell-culturing results showed that these Ca-P granules could promote cell adhesion, proliferation, and expression of a series of osteogenic genes. These findings demonstrated that these Ca-P granules had good bioactivity and pro-osteogenic ability, especially for BCP-G and TCP-G. Therefore, the porous spherical Ca-P bioceramic granules fabricated by the novel method show great potential to serve as good candidates for bone defect filling materials.

A vacuum insulation panel (VIP) is an inorganic composite insulation panel with a thermal conductivity of almost 0.004 W/(m•K) and a Class A fire resistance rating (noncombustible) that can achieve both heat preservation and fire protection. However, the application of VIPs in the construction industry still has many problems that need to be studied experimentally. In this paper, the building environment cabin is used to simulate wall insulation systems with three different insulation materials or construction methods, including pasted VIP boards, dry-hung composite VIP boards, and extruded polystyrene (XPS) insulation boards, and studying them in different working conditions, such as winter, summer, dry and wet, and assess the insulation performance under adverse conditions such as punctures. The conclusions are as follows: (1) In the thermal resistance test, considering that the heat flow on the surface of the envelope structure is susceptible to external disturbances, the average value of the heat flow on the indoor and outdoor surfaces of the structure should be taken into account when calculating the heat resistance of the envelope structure; (2) the test error of the working conditions under summer changing temperature conditions is greater than the constant temperature working conditions in winter; (3) the thermal resistance of the dry-hung VIP wall is greater than that of the pasted VIP wall because the static air interlayer behind the dry-hung VIPs causes the insulation effect to greatly increase; (4) the measured thermal resistance with the 50 mm pasted XPS is 32% lower than that of the wall with the 12 mm pasted VIPs; (5) after the VIP is punctured, its thermal resistance will be greatly reduced. In a wet environment, the extent of the decline will further increase.

Conventional biphasic calcium phosphate (BCP) bioceramics are facing many challenges to meet the demands of regenerative medicine, and their biological properties are limited to a large extent due to the large grain size in comparison with nanocrystalline of natural bone mineral. Herein, this study aimed to fabricate porous BCP ceramic spheres with nanocrystalline (BCP-N) by combining alginate gelatinizing with microwave hybrid sintering methods and investigated their in vitro and in vivo combinational osteogenesis potential. For comparison, spherical BCP granules with microcrystalline (BCP-G) and commercially irregular BCP granules (BAM, BCP-I) were selected as control. The obtained BCP-N with specific nanotopography could well initiate and regulate in vitro biological response, such as degradation, protein adsorption, bone-like apatite formation, cell behaviors, and osteogenic differentiation. In vivo canine intramuscular implantation and rabbit mandible critical-sized bone defect repair further confirmed that nanotopography in BCP-N might be responsible for the stronger osteoinductivity and bone regenerative ability than BCP-G and BCP-I. Collectedly, due to nanotopographic similarities with nature bone apatite, BCP-N has excellent efficacy in guiding bone regeneration and holds great potential to become a potential alternative to standard bone grafts in bone defect filling applications.

The LiFePO4/C composite with 3D-grape-bunch structure is successfully synthesized through a novel hydrothermal method. Sucrose is used as in-situ coating carbon source, and the hydroxylated MWCNTs are used as connecting carbon wires which can be embedded into the carbon coating via self-assembling of the hydrophilic groups to form 3D-grape-bunch structure. The influences of the 3D-grape-bunch structure on the morphology, structure and electrochemical performance of the LiFePO4/C composites are investigated by XRD, SEM, TEM, BET, galvanostatic charge/discharge tests, electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) tests. Especially, four kinds of the equivalent circuit models usually employed to analysis the EISs of LiFePO4 as cathode material for Li-ion battery are discussed, and the suitable equivalent circuit for fitting EIS of LiFePO4/C composite with 3D-grape-bunch structure is selected. The optimal LiFePO4/C composite with 3D-grape-bunch structure owing to its good conductive network and high graphitic degree (low ID/IG value) of residual carbon exhibits a stable and high reversible capacity of 160.5 mAh g−1 at 0.1C and 108.4 mAh g−1 even at 10.0C, and the cycling capacity retention rate reaches 99.9% over 60 cycles. Moreover, it also exhibits high conductivity, good reversibility and excellent stability in EIS and CV tests.

Phspho-olivine LiFePO4 was synthesized from the relatively insoluble lithium source Li2CO3, proper iron and phosphorus sources (n(Li):n(Fe):n(P)=1:1:1) by a novel hydrothermal method. Afterwards, the optimal sample was mixed with glucose and two-step calcinated (500 °C and 750 °C) under high-purity N2 to obtain the LiFePO4/C composite. The resultant samples were characterized by X-ray diffraction (XRD), atomic absorption spectrometry (AAS), scanning electron microscops (SEM), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS), elementary analysis (EA) and electrochemical tests. The results show that the optimal reaction condition is to set the reactant concentration at 0.5 mol·L−1, the reaction temperature at 180 °C for 16 h duration. During the reaction course, an intermediate product NH4FePO4·H2O was first synthesized, and then it reacted with Li+ to form LiFePO4. The optimized LiFePO4 sample with an average particle size (300 to 500 nm) and regular morphology exhibits a relatively high discharge capacity of 84.95 mAh· g−1 at the first charge-discharge cycle (0.1C, 1C=170 mA·g−1). Moreover, the prepared LiFePO4/C composite shows a high discharge capacity of 154.3 mAh·g−1 at 0.1C and 128.2 mAh·g−1 even at 5C. Besides it has good reversibility and stability in CV test.

A new carbon coating method for improving the performance of anode material of lithium ion battery is proposed in this paper. In this method, cetyl trimethyl ammonium bromide (CTAB) is used as dispersant and phenolic resin formed in situ on Li4Ti5O12-TiO2 is used as carbon precursor; thus, uniform coated sample with low carbon content is achieved. Three samples with different carbon contents are prepared, and their carbon content, morphology, structure, and electrochemical performance are investigated by thermogravimetry, scanning electron microscopy, transmission electron microscopy, X-ray diffraction, electrochemical impedance spectroscopy, and charge-discharge test. It is found that the sample with a carbon content of as low as 2.5 wt.% exhibits superior electrochemical performance. It delivers an initial capacity of 162.4 mAh g−1 with capacity retention of 95 % after 200 cycles at 1 C rate. When cycled at a higher rate of 5 C, the sample delivers a capacity of 148 mAh g−1 with no apparent capacity decaying after 90 cycles. The superior performance of the developed anode can be attributed to the uniform carbon coating.

The LiFePO4/C composite with a grape bunch structure was synthesized through the hydrothermal method at 170 °C for 7 h and followed by being fired at 750 °C for 4 h. Commercial Li2CO3, (NH4)2Fe(SO4)2 · 6H2O, and (NH4)2HPO4 were used as raw materials. Glucose was used as in situ coating carbon source, and the hydroxylated MWCNTs were used as connecting carbon wires which could be embedded into the carbon coating to form a uniform grape bunch structure. The resultant samples were characterized by X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscopy (TEM), energy dispersive spectrometry (EDS), elementary analysis (EA), Raman spectroscopy, and electrochemical tests. The results show that the grape bunch structure with a low disordered/graphene (D/G) ratio was found to be well dispersed in the LiFePO4/C composite, and a three-dimensional carbonaceous network was formed which could enhance the electronic conductivity of the LiFePO4/C composite remarkably. The resultant LiFePO4/C composite shows a high discharge capacity of 160.3 mAh g−1 at 0.1 C and 110.9 mAh g−1 even at 10 C, and the cycling capacity retention rate reaches 99.6 % over 60 cycles. Besides, it also exhibits high conductivity, good reversibility, and excellent stability in EIS and CV tests.

This paper presented a scientific study of the effects of four dispersion methods on the dispersion capability of nano La2O3 suspensions, which are ball milling, ultrasonic, ultrasonic followed by ball milling and ball milling followed by ultrasonic. For the purposes of comparing their dispersion capability, sedimentation test, Zeta-potential measurement test, particles size measurement test and transmission electron microscopy (TEM) test were carried out. Suspension ability coefficient was also defined with expectation to estimate the stability of nano La2O3 suspension through granularity size, and their relationship curve was worked out. The results showed that ultrasonic followed by ball milling enjoyed an excellent capability of dispersion for nano La2O3 suspension. Its mechanism was discussed, and breakage models of nano La2O3 particles were developed. The study results indicated that ultrasonic followed by ball milling could break through both the limits of ultrasonic dispersion size range and thermo-effect, and thus was able to overcome the problem of the secondary aggregation of nanoparticles. Moreover, aggregations could be further de-agglomerated. As a result, dispersion capability of nano La2O3 suspension could be improved more greatly by ultrasonic followed by ball milling. And its suspension stability was the best with the highest suspension ability coefficient of the nanoparticles. It was found in the experiment that there was almost no obvious phenomenon of stratification for the suspension with a little sediment after being deposited for 8 d.

The effects of local dipole on the chiroptical properties of chiral conjugated oligomers were investigated by comparative studies on two analogous chiral oligo(phenyleneethynylene)s: Myr-OPE-Br and Myr-OPE. Myr-OPE-Br carries local dipoles introduced by electron-accepting Br-groups and electron-donating chiral alkoxy-groups, while Myr-OPE only carries chiral alkoxy groups. The DSC thermogram of Myr-OPE-Br showed a glass transition at ∼80 °C and a cold crystallization centered at 120 °C, while Myr-OPE only showed a glass transition at ∼90 °C. Thermal annealing treatment showed significant effects on the absorption and CD spectra of spin-coated film of Myr-OPE-Br: with annealing above 100 °C, the absorption maximum exhibited an obvious red shift; the absorption bands displayed well-resolved vibronic structures; the CD spectrum was inversed compared to those with no annealing or annealing at 80 °C; and the gabs value of the annealed film increased with increasing annealing temperature and time. After annealing at 140 °C for 1 h, a maximum gabs value above 0.117 was observed for Myr-OPE-Br film. While for Myr-OPE, the thermal annealing treatment showed no obvious effect on both the absorption and CD spectra. The CD spectra of both the as-coated film and annealed film of Myr-OPE showed no obvious Cotton effect. The observed large g values as well as the thermochromic changes in the absorption and CD spectra of annealed Myr-OPE-Br films were attributed to the presence of local dipoles.

Three NiCoCrAlY coatings with Al content lower than 5 wt.% reinforced by different kinds of nano-particles with the same addition and one without nano-particles were prepared on a Ni-base super alloy using laser cladding technique. Hot corrosion of the NiCoCrAlY coatings in Na2SO4/K2SO4 (75:25, wt./wt.) mixture was performed at 1050 °C in static air. Results indicate that the hot corrosion resistance of the coatings with nano-particles is better than that of the one without nano-particles, among which the one with nano-CeO2 presented the best hot corrosion resistance. Effects of nano-particles on the hot corrosion behaviour were also discussed.

Different contents of nanometer Al2O3 particles (nano-Al2O3p) were added into laser cladding low Al NiCoCrAlY coatings to improve the oxidation resistance. The isothermal oxidation behavior of the coatings in air for 100 h at 1050 °C were investigated, and the effects and influencing mechanisms of nano-Al2O3p were discussed. The results showed that oxidation resistances of the nano-Al2O3p-added coatings are clearly better than that of the nano-Al2O3p-free one. The coating with 1 wt% nano-Al2O3p added showed the best performance. Its weight gain was 1.72 mg/cm2 after 100 h oxidation, which was only half the weight gain of the nano-Al2O3p-free coating. The duration required to reach the steady oxidation was only 1/20 that of the nano-Al2O3p-free coating, while the duration of the steady stage was 5 times longer than that of the nano-Al2O3p-free coating. With the addition of nano-Al2O3p, the oxidation resistance was improved by acceleration of Cr selective oxidation, inhibition of volatilization of Cr2O3 scales, improvement of oxide scale self-repairing capability, and blocking of micro channels for oxygen penetrating inwards. In particular, it was inferred that this blocking also has a significant effect on enhancing the oxidation resistance of other high temperature protective coatings such as non-volatile oxide scales.

In order to provide effective guarantee for the prediction of residual stress and deformation after welding process of large-sized aluminum alloy structures, temperature field and thermal efficiency during double-sided multi-layer TIG welding of aluminum alloy was studied. By integratedly considering temperature-depended material properties, convection, radiation, filling rate of solders, et al, numerical analysis about the form of molten pool and temperature field was given. Element birth and death technique was taken during the simulation. Double-sided multi-layer TIG welding experiment was carried out and sample of cross section of weld seam after welding was prepared. By trying different thermal efficiency for calculation, simulation result consistent with experimental result was obtained finally, making the present thermal efficiency as the aim result for study. Confirmation was given by comparing temperature value from experiment with simulation one.

Two regioregular poly(p-phenyleneethynylene-alter-m-phenyleneethynylene)s bearing (−)-trans-myrtanoxyl side groups with different substitution patterns were designed and synthesized, e.g. Myr-PMPE-1 and Myr-PMPE-2. In Myr-PMPE-1, the side chiral groups are distributed uniformly along the backbone. In Myr-PMPE-2, the distribution of the side chiral groups is alternatively crowded and loose. Both of these two polymers show no CD signal in solutions because of their good solubility. The investigations of chiroptical properties of these two polymers were carried out in the form of spin-coated films. The films were annealed above the glass temperature of the corresponding polymer, and the effects of annealing temperature and time on the properties of the films were investigated by UV-Vis absorption, fluorescence and circular dichroism spectra. The results show that annealing treatment had no significant effect on the properties of Myr-PMPE-1, including UV-Vis absorption, fluorescence and optical activity. The maximum absolute value of dissymmetry factor (|g max|) was 1.62 × 10−4. On the other hand, annealing treatment significantly affected the properties of Myr-PMPE-2. Without annealing or being annealed below 100°C, Myr-PMPE-2 films show almost no Cotton effect. In contrast, when annealed above 120°C, the absorption and emission of Myr-PMPE-2 films slightly red shifted with increasing annealing temperature and annealing time. Most importantly, the intensity of CD signals increased significantly and the optical activity of Myr-PMPE-2 films markedly increased. After annealing at 140°C for 4 h, the |g max| of Myr-PMPE-2 films was increased up to 3.07 × 10−3, about one order of magnitude higher than that of Myr-PMPE-1 films.

The influences of steam sterilization on the physicochemical properties of calcium phosphate (Ca-P) porous bioceramics, including β-tricalcium phosphate (β-TCP), biphasic calcium phosphate (BCP) and hydroxyapatite (HA) are investigated. After being steam sterilized in an autoclave (121 °C for 40 min), the porous bioceramics are dried and characterized. The steam sterilization has no obvious effects on the phase composition, thermal stability, pH value and dissolubility of β-TCP porous bioceramic, but changes its morphology and mechanical strength. Meanwhile, the steam sterilization leads to the significant changes of the morphology, phase composition, pH value and dissolubility of BCP porous bioceramic. The increase of dissolubility and mechanical strength, the decrease of pH value of the immersed solution and partial oriented growth of crystals are also observed in HA porous bioceramic after steam sterilization. These results indicate that the steam sterilization can result in different influences on the physicochemical properties of β-TCP, BCP and HA porous bioceramics, thus the application of the steam sterilization on the three kinds of Ca-P porous bioceramics should be considered carefully based on the above changed properties.

A multidisciplinary approach to the fabrication of biologically based magnetic monomers for biolimited forming is described. Rod-like Bacilli ccreus about 0.5 μ in diameter and 3–5 μm in length, were used as templates on which the ferromagnetic material was deposited by an electroless deposition method. Different electroless plating solutions were compared in detail and CoNiP solution was selected. During the deposition process, both dispersant and mechanical stirring were used to solve the problem of aggregation of bacterial cells so as to obtain a uniform plating layer. The CoNiP film on Bacilli cereus was a mixture of crystalline and non-crystalline in the phase structure and showed a good magnetism. The magnetic metallized bacterial cells could be manipulated with a magnetic field. Parallel arrays of these micro magnetic particles were achieved and they could rotate along with the magnetic field.

Uniform microparticles with a dimension of about 1 μm in diameter and several microns in length, were obtained by an electroless deposition technique of CoNiP on bacilli initiated by molecular palladium catalysts. Water-based magnetic fluid containing the small particles was treated with magnetic fields in order to obtain regular arrays of aligned particles. Using an optical microscope with camera system, real time visualization of the magnetic particles was carried out. Both array and chain-like cluster formation of particles under magnetic field were observed. The interaction with the magnetic fields was also analyzed.

Bacteria cells with different standard shapes are well suited for use as templates for the fabrication of magnetic and electrically conductive microstructures. In this paper, metallization of bacteria cells is demonstrated by an electroless deposition technique of nickel-phosphorus initiated by colloid palladium-tin catalyst on the surfaces of Citeromyces matritensis and Bacillus cereus. The activated and metallized bacteria cells have been characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X-ray diffraction analysis (XRD). Results showed that both Citeromyces matritensis and Bacillus cereus had no deformation in shape after metallization; the metallized films deposited on the surfaces of bacteria cells are homogeneous in thickness and noncrystalline in phase structure. The kinetics of colloid palladium-tin solution and electroless plating on bacteria cells is discussed.