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Abstract: Monodisperse and spherical Eu-doped TiO2 nanodots were prepared on substrate by phase-separation-induced self-assembly. The average diameters of the nanodots can be 50 and 70 nm by changing the preparation condition. The calcined nanodots consist of an amorphous TiO2 matrix with Eu3+ ions highly dispersed in it. The Eu-doped TiO2 nanodots exhibit intense luminescence due to effective energy transfer from amorphous TiO2 matrix to Eu3+ ions. The luminescence intensity is about 12.5 times of that of Eu-doped TiO2 film and the luminescence lifetime can be as long as 960 μs.

Advanced high strength steels (AHSS) are typically loaded in a multiaxial stress state during forming process and service. However, the deformation mechanism under multiaxial loading is not clarified, which limits the optimization of sheet metal forming. In particular, due to instability, biaxial compression loading of single thin plate has not been reported, which results in unclear evolution of the yield surfaces in the second, third and fourth quadrants of σ11-σ22space and corresponding deformation mechanisms. Therefore, the deformation mechanism of AHSS thin plates under biaxial loading was systematically investigated in the complete σ11-σ22space using a specially designed cruciform specimen and buckling prevention fixture in the current work. The mechanical properties of dual-phase (DP780) steel under different loading paths were studied by uniaxial tension, uniaxial compression, and biaxial loading tests. There is an obvious yield strength difference between the first quadrant and the third quadrant in the σ11-σ22space. In the second and fourth quadrants of σ11-σ22space, the compression part makes a greater effect on the yield behavior of the material than the tension part. More specifically, dislocation slip is activated earlier at the boundary under compression loading, resulting in earlier yielding of the material. Based on the analysis of the Taylor factor, the activation of slip systems of DP780 steel before and after deformation is clarified. In addition, a detailed analysis of the microstructure and texture evolution in DP780 steel after deformation is conducted, and a correlation between texture evolution and loading paths is established. It is found that the compression part under biaxial loading results in more grains with low Taylor factor and promotes the transformation of the initial texture to copper or rotated copper texture in DP780 steel.

Pore pressure plays a crucial role in various fields, including geology, petroleum engineering, hydrology, and carbon capture, utilization, and storage (CCUS). Traditional pore pressure prediction methods, which rely on physical models, often fail to meet the required accuracy standards due to their inflexibility and technical parameterization. Although machine learning methods have been increasingly used for pore pressure prediction, they struggle to integrate domain-specific knowledge and capture the inherent temporal dynamics of the data, resulting in suboptimal prediction accuracy. To address these limitations, this study introduces the Knowledge-Aware TFT model, which determines the key parameter attributes for pore pressure prediction by comprehensively analyzing well logging data, rock mechanics theory, and pore pressure evolution theory. Additionally, the model effectively captures the temporal dynamic characteristics of the data, thereby enhancing the accuracy of pore pressure prediction. To validate the model's accuracy, uncertainty theory is employed to evaluate the experimental results, providing a description of the uncertainty associated with pore pressure prediction and supporting credibility assessment. A case study involving three vertical wells in Block X, China, compares the Knowledge-Aware TFT model with SVM, XGBoost, MLP, and LSTM models, further confirming its superior prediction accuracy (Rˆ2=0.997, RMSE=0.135) and demonstrating its practicality in pore pressure prediction. In conclusion, the proposed pore pressure prediction model not only improves prediction accuracy but also achieves excellent results in practical applications, making it a viable alternative to traditional technologies.

ABSTRACTBackgroundStudies have shown acute flares of chronic hepatitis B (CHB) might be related to immunologic changes that occur during pregnancy. However, the indicators for predicting acute flares of CHB among pregnant women still need further study. We aimed to distinguish the relevance between serum levels of HBcrAg and acute flares of CHB in pregnant women in the immune-tolerant phase of chronic HBV infection after short-course antiviral therapy.MethodsA total of 172 chronic HBV-infected pregnant women who were judged to be in the immune-tolerant phase were recruited in our research. All patients received short-course antiviral therapy with TDF. The biochemical, serological, and virological parameters were measured using standard laboratory procedures. The serum levels of HBcrAg were tested by ELISA.ResultsFifty-two (30.2%) out of 172 patients had acute flares of CHB. At postpartum week 12 (TDF cessation), serum HBcrAg (OR, 4.52; 95% CI, 2.58–7.92) and HBsAg (OR, 2.52; 95% CI, 1.13–5.65) were associated with acute flares of CHB. The serum HBcrAg levels were beneficial for confirmation of patients with acute flares of CHB, with an area under the ROC curve of 0.84 (95% CI, 0.78–0.91).ConclusionsFor pregnant women with chronic HBV infection in the immune-tolerant phase, serum HBcrAg and HBsAg levels at postpartum week 12 were associated with acute flares of CHB after short-course antiviral therapy with TDF. The serum HBcrAg level can correctly identify acute flares of CHB and may be a predictor of the need for continuing antiviral therapy after 12 weeks postpartum.

ABSTRACTA 40-year-old Chinese female patient, with radiation-induced brain necrosis after radiosurgery, was treated 6 times with a single dose of 200 mg (3.27 mg/kg) bevacizumab each time, and with an interval of 12–16 weeks between each treatment. Neurological symptoms such as dizziness, fatigue, and headache disappeared after each administration of bevacizumab. The results suggest that repeated bevacizumab treatment using a low-dose and long-dosing interval may significantly alleviate radiation necrosis and its symptoms.

The outcome of recurrent brain metastasis is dismal. This study aims to assess the clinical outcomes and toxicity of reirradiation as a salvage treatment for progressive brain metastasis in patients with advanced breast cancer. Between July 2005 and September 2014, the medical records of 56 patients with brain metastasis from breast cancer were retrospectively reviewed. Of these patients, 39 received whole-brain radiotherapy (WBRT) followed by stereotactic radiosurgery (SRS) reirradiation (Group 1), and 17 received SRS followed by WBRT reirradiation (Group 2). Overall survival (OS) and brain progression-free survival rates/times were calculated using the Kaplan-Meier method. Prognostic factors were evaluated using the Cox proportional hazards model. Change in neurologic function was also assessed. The median OS was 10.8 months (range, 1.3-56.8 months). In Group 1, the median PFS time (PFS-1) was 6.5 months and the OS time was 11.4 months. Multivariate analysis revealed that longer OS was significantly associated with a high Karnofsky performance score (KPS) (P = 0.004), controlled extracranial metastasis (P = 0.001) and a good response to reirradiation (P = 0.034). In Group 2, the median PFS time (PFS-2) after reirradiation was 8.5 months and the OS time was 10.8 months. Multivariate analysis revealed that longer OS was significantly associated with a high KPS (P = 0.018). The majority of the patients had improved or stable neurological function. Reirradiation is an effective and a safe treatment for patients with brain metastases from breast cancer. It might delay the progression of intracranial disease and improve neurological function. A suitable patient selection for reirradiation was suggested.

Capacitive deionization (CDI) is a novel electrochemical water-treatment technology. The electrode material is an important factor in determining the ion separation efficiency. Activated carbon (AC) is extensively used as an electrode material; however, there are still many deficiencies in commercial AC. We adopted a simple processing method, ball milling, to produce ball milled AC (BAC) to improve the physical and electrochemical properties of the original AC and desalination efficiency. The BAC was characterized in detail and used for membrane capacitive deionization (MCDI) and flow-electrode capacitive deionization (FCDI) electrode materials. After ball milling, the BAC obtained excellent pore structures and favorable surfaces for ion adsorption, which reduced electron transfer resistance and ion migration resistance in the electrodes. The optimal ball-milling time was 10 h. However, the improved effects of BAC as fixed electrodes and flow electrodes are different and the related mechanisms are discussed in detail. The average salt adsorption rates (ASAR) of FCDI and MCDI were improved by 134% and 17%, respectively, and the energy-normalized removal salt (ENRS) were enhanced by 21% and 53%, respectively. We believe that simple, low-cost, and environmentally friendly BAC has great potential for practical engineering applications of FCDI and MCDI.

Membrane capacitive deionization (MCDI) is an efficient desalination technology for brine. Penicillin fermentation residue biochar (PFRB) possesses a hierarchical porous and O/N-doped structure which could serve as a high-capacity desalination electrode in the MCDI system. Under optimal conditions (electrode weight, voltage, and concentration) and a carbonization temperature of 700 °C, the maximum salt adsorption capacity of the electrode can reach 26.4 mg/g, which is higher than that of most carbon electrodes. Furthermore, the electrochemical properties of the PFRB electrode were characterized through cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) with a maximum specific capacitance of 212.18 F/g. Finally, biotoxicity tests have showed that PFRB was non-biotoxin against luminescent bacteria and the MCDI system with the PFRB electrode remained stable even after 27 adsorption—desorption cycles. This study provides a novel way to recycle penicillin residue and an electrode that can achieve excellent desalination.

Understanding the energy transition which is influenced by doping ions and host materials in the upconversion (UC) physical processes is of vital importance for further optimizing performance and extending applications of UC materials. In this work, we have selected 4% Er-doped perovskite PbTiO3(PTO) nanofibers as a model system to explore the effects of tetragonality and polarization on UC photoluminescence (PL) properties. By means of in situ X-ray diffraction, the tetragonality and polarization of these nanofibers have been determined to gradually decrease with an increasing of the temperature from 50 to 300 K, leading to obvious enhancements in UC green band emission of 523 nm (about 43 times) and red band emission of 656 nm (about 8 times), in contrast to the decreased green and red UC intensities in Er-doped BaTiO3or PTO particles. Moreover, the significant enhancement in the intensity ratio of green to red bands from 0.17 to 0.86 has been achieved, indicating that the emission enhancement is highly wavelength-dependent. On the basis of in situ UC decay curves from 50 to 300 K, the UC lifetimes of the 4S3/2and 4F9/2level have been derived to be 128.04 ± 0.47 μs and 278.10 ± 1.07 μs at 50 K, respectively, and the values are basically maintained as the temperature increases. The observed UC phenomena in Er-doped perovskite PTO nanofibers can be ascribed to an assisted effect of the low-energy E(1TO) phonon on the UC process. Such phonon energy can be easily tailored by the tetragonality and polarization; thus, a modification of UC emissions in Er-doped PTO nanofibers has been achieved. The findings in this work could provide new insights into understanding the UC process in perovskite oxides and offer an opportunity to tune UC emission by an external field, such as an electric field, in addition to temperature.

Reflective displays that rely on ambient light as opposed to an internal light source have been making inroads for a variety of important applications, especially those involving mobility where power usage must be aggressively controlled. The underlying color rendering strategies for both reflective and emissive displays have largely been the same, combining three fixed, primary color subpixels to compose the rich gamut that users expect. The result, for reflective color displays, is unfavorable brightness/gamut performance since each of the color subpixels absorbs roughly 2/3 of the incident white light. We demonstrate a new technology that we call the single mirror interferometric display that overcomes such limitations with pixels whose reflectance properties can tune through a continuum of colors, including high contrast black and white reflectance states. We use an effect that we call interferometric absorption in which a thin absorbing metal layer in front of a highly reflective mirror surface selectively absorbs different colors, depending on the gap that separates the two. The gap is controlled by electrostatic actuation in a relatively simple micro-electro-mechanical-system structure. We describe this elegant and powerful color rendering principle and present experimental results for the basic pixel device as well as early system demonstrations.

ABSTRACTOut-of-field tumor response, which is also called abscopal effect, bystander effect, or non-target effect, can be regarded as localized irradiation induced systemic antitumorigenic effects, indicating shrinkage of a tumor distant from the irradiated site. Although abscopal effect has been documented in several tumor types, it is a very rare phenomenon which is clinically reported in non-small-cell-lung carcinoma (NSCLC). Herein, we present a rare case of patient with NSCLC with 2 lesions in the upper lobe of left lung who, after receiving stereotactic ablative radiation therapy (SABR) to one of the tumors, had an apparent spontaneous regression of the other mass in the lung, suggestive of a radiation-induced abscopal effect.

PVA/PVP-assisted hydrothermal method was used to prepare single-crystal pre-perovskite PbTiO3 (PP-PT) nanofibers, in which polyvinyl alcohol (PVA) and polyvinyl pyrrolidone (PVP) acted as surfactants. Subsequently, poly (vinylidene fluoride)/ pre-perovskite PbTiO3 nanofibers (PVDF/PP-PT) nanocomposite thin films were successfully fabricated by a spin-coating method. The test results showed that PP-PT nanofibers had a good distribution in PVDF matrix. Moreover, α-phase coexisted with β-phase in the PVDF and PVDF/PP-PT nanocomposite thin films. The dielectric properties of the PVDF/PP-PT nanocomposite thin films were measured as a function of frequency in the range of 5 kHz to 5 MHz. It is worth noting that the dielectric constant of nanocomposite thin films increased with increasing the weight ratio of PP-PT nanofibers in the low frequency range. By contrast, the dielectric constant of PVDF/PP-PT nanocomposite thin film which contained 20% PP-PT nanofibers was 43.7% larger than that of pure PVDF thin film (εr = 6.77) at 5 kHz, and the loss tangent was ~0.03.

A brushlike PbTiO3(PTO)/ZnO nanocomposite with ZnO nanowires (NWs) grown epitaxially on the surface of single-crystal ferroelectric tetragonal PTO NWs is successfully fabricated onto a flexible substrate via a two-step hydrothermal process. In this nanocomposite, a ZnO NW grew along [0001] on the (101) plane of the core PTO NW with a lattice mismatch of 1.06% to form an effective ferroelectric/semiconductor interface. It is found that the ultraviolet photoluminescence emission of the nanocomposite could be easily tuned by its bending curvatures at room temperature. This intriguing phenomenon can be understood by the bending-induced polarization field from the PTO NW, which could reduce the bending degree of the energy band of the ZnO NWs through the interface. Throughthe design of an effective interface, this kind of ferroelectric/semiconductor nanocomposite may find potential applications in sensor and piezophotonic nanodevices.

The Er-doped preperovskite and perovskite single-crystal PbTiO3(PTO) nanofibers with a series of doping concentration (0–4 mol %) were successfully synthesized by hydrothermal method and solid state phase transformation method, respectively. The XRD, XPS, and Raman results indicated that Er3+occupied Pb2+site in preperovskite PTO and Ti4+site in perovskite PTO nanofibers. The photoluminescence (PL) measurements indicated that only the strong green emission corresponding to the preperovskite PTO host matrix was observed, whereas up-conversion (UC) emission under infrared excitation (980 nm) was absent. In contrast, the strong green emission (at 524 and 554 nm) and the weak red emission around 670 nm of Er3+occurred in the PL and UC PL processes of Er-doped perovskite PTO nanofibers. The distinguished difference in these two kinds of nanofibers might be attributed to the substitution sites and chemical environments of Er3+. It is suggested that such Er-doped single-crystal perovskite PTO nanofibers could be interesting objects for applications in mechanical–electrical luminescence such as electric field modulation luminescence and mechanoluminescence.

There is heterogeneity in cancer patients’ responses to immune checkpoint inhibitors (ICIs), including hyperprogression, which is very rapid tumor progression following immunotherapy, and pseudoprogression, which is an initial increase followed by a decrease in tumor burden or in the number of tumor lesions. This heterogeneity complicates clinical decisions because either premature withdrawal of the treatment or prolonged ineffective treatment harms patients. We presented two patients treated with ICIs with heterogeneous responses. One patient had Merkel cell carcinoma in the right thigh, and the other had nasopharyngeal squamous carcinoma. The first patient was treated with sintilimab and the second with sintilimab combined with abraxane. In the first patient, subcutaneous lesions grew substantially after the first cycle of treatment with sintilimab. In the second patient, subcutaneous lesions grew gradually after the second cycle of treatment with sintilimab combined with abraxane. In both cases, biopsy examination confirmed that newly emerged lesions were metastases of the primary tumor. These two cases remind clinicians that when subcutaneous nodules appear after treatment with ICIs, pathological biopsy is needed to determine the nature—pseudoprogression or rapid progression—of the disease course.

Rhombohedral bismuth ferrite (BiFeO3) powders were hydrothermally synthesized by using C6H8BiNO7 and Fe (NO3)·5H2O as precursors, KOH as a mineralizer and poly sodium-p-styrenesulfonate (PSS) as an additive. The phase formation and morphology of the as-prepared powders were characterized by X-ray diffraction,raman spectroscopy, and field-emission scanning electron microscopy. In order to investigate the effects of PSS, a series of experiments were performed by changing the introduced amount of PSS and the hydrothermal reaction time. The results showed that the introduction of the PSS leads to the synthesized bismuth ferrite changes from the mixture of Bi2Fe4O9 and BiFeO3 to pure rhombohedral BiFeO3. Corresponding to the phase composition evolution, the particle morphology alters from nanosheets to microparticles. The magnetic properties of single-crystalline BiFeO3 powders were also characterized. Based on the experimental results, the phase formation mechanism of the rhombohedral BiFeO3 hydrothermally synthesized assisted with PSS was discussed.

Pre-perovskite PbTiO3 nanofibres were synthesized by hydrothermal method with four butyl titanate ((C4H9O)4Ti) and lead nitrate (Pb (NO3)) as the main precursors and Tetramethylammonium Hydroxide (TMAH) as mineralizer. X-ray diffraction (XRD), Raman, Scanning Electronic Microscopy (SEM), Transmission electron microscopy (TEM), high-resolution TEM (HRTEM), and the corresponding selected area electron diffraction (SEAD) were used to characterize the crystal structure and morphology of the obtained products. The results showed that the nanofibers are of a few to tens micrometer at length size, and 50~300 nm at diameter size. Based on the experimental results, the effect of Tetramethylammonium Hydroxide (TMAH) was simply discussed.

Perovskite lead titanate crystals with various morphologies were successfully synthesized via a hydrothermal reaction route with different lead sources. X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and high-resolution transmission electron microscopy (HRTEM) were employed to characterize the phase composition and the morphology of the synthesized products. In order to investigate the effect of the lead source on the phase formation and morphology evolution of the synthesized pervoskite PbTiO3 crystals, PbO, PbF2, PbSO4 and Pb (CH3COO)3 ·3H2O, were used as starting precursor lead source introduced into the hydrothermal reaction system, respectively. Accordingly, perovskite PbTiO3 brken cubes, irregular particles, cubic particles, and microplates were obtained, respectively. Based on the experimental results, the effect of lead source was simply discussed.

Human visual system has the property of perceiving the object color to remain constant regardless of the prevailing illumination. However, digital cameras usually lack this capability, and the captured images are digitally corrected to discount the color of the scene light based on the estimated illuminant. Illumination estimation might be erroneous in some artificial or chromatic lighting conditions. A method was proposed to correct digital photos captured with a smartphone camera using the smartphone owner's face as the reference. Taking the advantage of the latest smartphones with two build-in cameras, we could use the front camera to capture the smartphone owner's face and compare with the saved reference face image in order to estimate the scene illuminant. After that, we could properly adjust the capture setting for the main camera in order to take a decent target image; or we could automatically correct the target image based on the estimated illumination by comparing two face images. The method was implemented on the iOS mobile platform. Experimental result shows that the adjusted images using the proposed method are generally more favorable than the pictures taken directly by the default camera application.

We present a stochastically seeded halftoning method with parametric control of dot shapes as well as seed placement adaption to local image structure. While the literature on other randomly structured screens (blue noise, green noise, FM) is quite extensive, there is very little discussion on optimization of dot shape for robustness or preferred tile appearance. The halftoning method that we introduce defines dot centers as seeds that are placed, typically in a random high spatial frequency configuration. Spot functions are defined about these randomly placed seeds, where the spot function allows control of dot cluster growth, touch points, cluster angle, and eccentricity. The spot function can also be applied to regular and irregular polygonal halftone tiling. The seed adaption aspect of the halftoning method allows for better edge rendition than conventional isotropic methods.

A method is provided for embedding a UV fluorescent watermark in a color halftone image printed on paper. The described method implements two different strategies to halftone a watermark region and a background region. One strategy uses dot-on-dot halftoning to maximize the usage of black ink and minimize ink dispersion, while the other strategy uses successive-filling halftoning to maximize ink dispersion. An accurate color look-up-table (LUT) is built to directly transform the colorant values for one halftoning strategy to the colorant values for the other strategy. With the color transformation applied on one region, the binary outputs in both watermark and background regions halftoned with different strategies exhibit similar color appearance under normal lighting condition. However, under UV illumination, due to the fluorescent effect caused by different paper coverages in two regions, the embedded watermark becomes clearly visible.

A halftone configuration is presented that utilizes three or four rotated hexagonal screens, or more precisely, screens with hexagonally tiled clusters, for moiré-free color printing. Halftone designers consider many options to deliver a screen with desirable characteristics, and often must settle for less than desirable results. The present method presents a new option with several beneficial properties compared to conventional square-cell-based screens. Hexagonal screens can appear to have smoother texture. Due to differences in packing geometry and touch point geometry, hexagons have the potential to possess different tone reproduction characteristics, which may be favorable for some marking processes. A fourth screen (e.g., yellow) can be included moir�-free, thereby avoiding problems associated with stochastic solutions for yellow. We also present a corresponding parametrically controlled hexagonal halftone spot function that allows for optimization of dot touch points and provides compact growth. The optimized touch points can prevent a tone reproduction bump, while the compact growth throughout the gray range ensures maximum stability. Examples are provided.

Porous NiO-Ce0.8Sm0.2O1.9 (NiO-SDC) ceramics with homogeneous pore distribution were prepared using polystyrene (PS) spheres as pore templates. NiO-SDC powders were synthesized by a glycine-nitrate method, ultrasonically mixed with PS spheres in ethanol, dried and then pressed into green pellets. The pellets were sintered to yield porous NiO-SDC ceramics. The effects of the sintering temperature on the microstructure and mechanical strength of the ceramics were investigated. NiO-SDC ceramics sintered at 1200 and 1350°C have interconnected pore structures and high compression strength. When single cells were fabricated using porous NiO-SDC ceramics as anode-supported layers, the peak power density of the cells at 600°C was 333 and 353 mW·cm−2 for ceramics sintered at 1200 and 1350°C, respectively. The results indicated that these porous ceramic materials are promising for anode substrates for solid oxide fuel cells. [Copyright &y& Elsevier]

The synthesis of aluminum titanate solid solution (Al2(1-x)MgxTi1+xO5, x=0, 0.1, 0.2) powders was realized by solid state reaction method using fine commercial α-Al2O3, TiO2 and MgO powders as raw materials. The effect of the introduced amount of MgO on the phase formation of aluminum titanate solid solution was investigated by XRD following the phase evolution. It was revealed that the introduction of MgO strongly affects the formation of Al2(1-x)MgxTi(1+x)O5 solid solution. The easily formed MgTi2O5 acts as the nucleus prompting the formation and lowering the synthesis temperature. The microstructure and properties of the solid solution ceramics were also studied by SEM and measuring the fracture strength and the thermal expansion coefficient.

Aluminum phosphate is one of the best inorganic binders, and the addition of chromium oxide can improve the properties of the binder. In this work, the phase evolutions in chromium phosphate system and aluminum-chromium-phosphate system during heat-treatment were investigated. The initial binder solutions were prepared by dissolving Al(OH)3 and Cr2O3 in aqueous H3PO4 solution. The binder solutions consolidated at 100°C. The as-consolidated products were heated at different temperature. The experimental results showed the phase evolution of the consolidated products as: amorphous phase in 300~800°C, Cr(PO3)3 and Cr4(P2O7)3 in 900~1200°C for chromium phosphate system binder; amorphous phase in 300~1000°C, Cr(PO3)3 and AlPO4 in 1100°C, Cr4(P2O7)3 and AlPO4 in 1200°C for aluminumchromium- phosphate system binder. The addition of chromium oxide demonstrates to strengthen amorphous network, which further improves the thermal stability.

Bone-Like Microstructured β-TCP/Collagen Layer on Fluoridated Hydroxyapatite Coating, which could able to create a biodegradation layer with enhancing bone formation, was prepared in wet synthesis. The formation of the layer was characterized and discussed.

It is known that the organic molecules can provide effective means to tailor the surface properties of the biodegradable ceramic. In this paper, a long-chain organic silane- Octadecyltrichlorosilane(OTS) was used as coupling agent and hydroxyapatite(HA) was the candidate ceramic. Samples were characterized by means of XPS technique. XPS results indicated that Si-O-P bond was formed on the HA surface after surface-modification, which means OTS was grafted onto the HA surface through covalent bond , XPS results also showed that by regulating the surface-modification process Si(Atomic percentage) content on HA surface could be changed from 0 to 2.88%.

Two starting collagens, sponge and floc collagen, were used to prepare collagen/tricalcium phosphate (TCP) composites. The resulting composites were porous and had 200μm pore size. However, there was a difference in the microstructure of the pore walls for the composites derived from the two collagens, the pore walls in sponge collagen/TCP composite were still porous and had 200 nm micropores size, TCP particles were trapped in collagen matrices. While floc collagen/TCP composite had smooth and dense walls in which TCP particles were embedded. The difference could be attributed to the starting collagen with different status. Sponge collagen has a soft structure, which easily becomes disassembled fibrils during alkali treatment, the disassembled fibrils are integrated again to form a dense morphology for pore walls after freeze-drying. While floc collagen has already a low disassembly degree, the alkali treatment could not be able to separate the fibrils, this remains as micropores in pore walls after freeze-drying. Both porous composites are significant in bone tissue engineering or regeneration. MTT test results showed the two composites had good cytocompatibility, and sponge collagen/TCP composite was somewhat better than floc collagen/TCP composite, which could result from that micropores derived roughness in pore walls of sponge collagen/TCP composite is suitable for cell growth.

Porous β-tricalcium phosphate (β-TCP)/ Poly L-lactic acid (PLLA) composites were prepared by thermally induced phase separation method. The results showed that the composite had an interconnected pore structure with ～200μm macropores. The inorganic particle content in the composites varied from 50% to 80% and these particles were homogeneously dispersed in PLLA matrix. The composites obtained in this study could act as a promising scaffold for bone tissue engineering because of the pore structure and the mechanical properties.

In this work, nano-sized strontium containing tricalcium phosphate (SrTCP) particles with different strontium content were prepared using co-precipitation method in an ice-water bath and then 800ºC calcination. The AAS results show that the relative Sr/(Sr+Ca) ratios are consistent with the amount of strontium added in the initial solution but larger than the designed molar percentage. The TEM micrographs demonstrate the size of the SrTCP particles is in the region of 150-400 nm while the pure TCP particle is about 500nm. The SEM photographs show the morphology of the particles before and after incorporation of strontium and it is obvious that the particle size of SrTCP decrease with the increasing of strontium content.

Stearic acid was utilized to modify biphasic alpha-tricalcium phosphate (α-TCP)/hydroxyapatite (HA) powders in the ethanol. The results showed that the dispersion of biphasic α-TCP/HA powders (BCPs) in non-polar matrix improved. And the released content of Ca2+ and PO4 3- of the BCPs soaked in the NaAc-HAc buffer solution (pH 5.0) was almost same as that before modification. Stearic acid could modify the suface properties of BCPs and would not obviously affect their biological characteristics, which affords a good groundwork of application of calcium phosphates powders.

In order to optimize the dissolution resistance, cell attachment and Ca and P releasing ability of the calcium phosphate coatings, Hydroxyapatite/fluorapatite (HA/FA) biphasic coatings are prepared and characterized. Ultrasonically dispersing of HA powders in the mixed ethanol solution of Ca(NO3)2, P2O5 and HPF6, to form a “colloidal sol” for dip coating. The coatings are prepared on Ti6Al4V substrate by dip coating, 150oC drying and 600oC firing. The coatings are characterized by X-ray Diffractometer for the crystalline phase, X-ray Photoelectron Spectroscopy for chemical composition and Scanning Electron Microscopy for the surface morphology. The results show biphasic HA/FA coatings with homogenous distribution of HA particle in the FA matrix can be obtained. The nominal F content of the coatings decreases with the increasing amount of HA, and the surface morphology is rough. These demonstrate the obtained biphasic HA/FA coatings are suitable to response to cells, accelerating bone formation.

β-tricalcium phosphate (β-TCP)/collagen composites are in the limelight for their biomedical applications. It is believed that joint status of β-TCP particles with collagen fibrils plays key roles in both osteoconductivity and biodegradability of composites. In this work, the influence of acidity during synthesis on the joint status between nano-sized β-TCP particles and collagen fibrils is investigated. The composites are characterized by X-ray diffractometer and Field Emission Scanning Electron Microscope. The results show that the joint status of nano-sized β-TCP particles with collagen fibrils in the composites depends on the acidity in collagen suspensions. A desired joint status with obvious disassembled collagen fibril, good particle dispersion and strong boding between the particles and the fibrils could be obtained when acidity of the collagen suspension is pH 2.

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Nano-sized zinc containing β-tricalcium phosphate (ZnTCP) powders were synthesized by a co-precipitation method. The co-precipitation took place in an ice-water bathed beaker, after further washing, freezing, lyophilizing and calcining at 800ºC, the precipitates transformed to ZnTCP powders. The XRD pattern of the ZnTCP powders demonstrated a pure β-TCP phase. TEM observation revealed the particle size is about 100-120nm, which is favorable for TCP particles to form composites, such as polymer based composite, and as well to attain a desired microstructure. It was found zinc incorporation could eventually result in the decrease of particle size, thus be beneficial for its further application.

Nano-sized hydroxyapatite (HA) chloroform suspensions were firstly prepared by reactions in an emulsion system of Ca(OH)2-H3PO4-chloroform-lecithin, then, HA/PMMA composites with well dispersed HA could be obtained by adding PMMA into the suspension. The residual water in the HA suspension could lead to a porous surface which demonstrated better bioactivity in in vitro test. The residual water could cause HA particles to exist on pore walls during the composite formation, resulting in the increase of the HA amount per unit surfac

Submicron α-tricalcium phosphate (α-TCP), β-tricalcium phosphate (β-TCP) and biphasic α/β-TCP powders were prepared by an amorphous calcium phosphate (ACP) precursor way. For the biphasic TCP powders, primary particle size was 300nm, α-TCP and β-TCP primary particles were homogeneously mixed in the submicron powders. When the TCP powders were soaked in acetate buffer solution with pH 5, the Ca ion concentration in the soaked solutions and the resulting morphology variations were measured and observed. The results showed that the dissolution behavior of the biphasic TCP powders was different from α-TCP and β-TCP, and had a higher dissolved Ca ion concentration. This is attributed to a high supersaturation which is cased by the distribution homogeneity of two phase primary particles in submicron powders. These demonstrate the biphasic TCP to have potential to extend biological applications of Ca phosphates.

An amorphous calcium phosphate precursor way was utilized to prepare submicron biphasic α-tricalcium phosphate (TCP)/hydroxyapatite (HA) powders. The results showed that the addition of carbonate during the precipitation reaction could eventually lead to the formation of HA phase in the resulting powders, and even determine the relative content of HA to the range from 0 percent (pure α-TCP) to 100 percent (pure HA). Similarly, the particle size of the resulting biphasic powders depended on the carbonate content, ranging from 100nm to 500nm. The biphasic Ca phosphate with tailored α-TCP/HA ratio could be a new combination of calcium phosphate for promoting early bone formation.

Thermally induced phase separation technique was utilized to fabricate biodegradable poly(l‐lactic acid) (PLLA) macrocellular foams which were capable of being applied in tissue engineering. The block copolymer Pluronic F127 composed of (polyethyleneoxide)‐(polypropyleneoxide)‐(polyethyleneoxide) [(PEO)‐(PPO)‐(PEO)] was used as a porogen. Water/dioxane mixtures with different volume ratios were used as solvents. The addition of Pluronic F127 could induce an appearance of large pores (50–200 μm) besides small pores (10–20 μm) or a change from a solid–liquid phase separation to a liquid–liquid phase separation. The role of Pluronic F127 depends on the water/dioxane ratios in the PLLA/dioxane/water system. The X‐ray diffraction patterns and porosity measurement results showed that Pluronic F127 was crystallized and existed on the pore wall. The effect of Pluronic F127 on changing pore structure is attributed to the occurrence of the interaction of the lipophilic PPO blocks in Pluronic F127 with PLLA clews, consequently, this results in PLLA aggregation and early phase separation on cooling. Copyright © 2004 John Wiley & Sons, Ltd.

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While diffraction-pattern sampling has been widely applied in the classification of patterns, still its usage has been limited somewhat by the need to devise rather sophisticated algorithms. In this paper we describe sorting or classification of a variety of patterns with commercially available neural-network software together with the ring–wedge photodetector to supply optical transform data for the input neurons. With this combination of neural networks and diffraction-pattern sampling it is no longer necessary to write specialized software. The training and testing methodology is carried out for this new system, and excellent results are obtained for sorting thumbprints. In sorting thumbprints the neural network can be trained for orientation-independent or wide-scale size-independent classifications by use of ring-only or wedge-only input neurons, respectively. Separate experiments are described for the sorting of particulates. Again, these are cases in which writing appropriate software based on diffraction theory would be extremely difficult. Two interesting novel neural networks are obtained: one is for real-time control of a submicrometer colloidal suspension of CdS, and the second is for concentration measurements of 2.02-μm polyvinyltoulene spheres in methyl alcohol. Widespread new applications are predicted for this hybrid system that combines diffraction-pattern sampling and the neural network.