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This article presents a model for simulating the X-ray transmission properties of a polycapillary X-ray lens in which the capillaries are arranged in a layered hexagonal structure. Each layer consists of hexagonally shaped capillary bundles which are arranged symmetrically around a centerline, and the capillary radius varies with the layer. The transmission efficiency of X-rays in different layers is studied, and by designing the capillary radius, a uniform X-ray intensity distribution is generated at the output of the polycapillary parallel X-ray lens, which has remarkable differences with the distribution of a conventional polycapillary parallel X-ray lens. In addition, several common defects in the manufacturing process of the polycapillary lens are simulated.

Two paint fragments from an oil pipeline were analyzed with a confocal three-dimensional micro-X-ray fluorescence (3D-XRF) spectrometer. The depth distributions of iron (Fe), titanium (Ti) and zinc (Zn) metal elements were obtained based on confocal 3D-XRF analysis. The quantitative element results were obtained by scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDS). The corrosion process of the oil pipeline was investigated based on the experimental results, which provided information for designing an oil pipeline protection scheme.

The insulating performance of oil-impregnated pressboard decreases due to partial discharges (PDs). Although methods of pressboard life assessment and its dependency on PD have been extensively investigated, little is known about the microscopic process and the physical mechanism of PD-induced pressboard failure. This study investigated the electrical aging characteristics of pressboard from the perspective of physico-chemical analysis. Pressboard samples were treated with the chosen numbers of PDs to induce electrical aging and the chemical composition of the PD-treated pressboard was analyzed. The results revealed the generation of carbonyl groups and the consumption of hydroxyl groups on the surface of the pressboard after PD treatment. These groups were generated by the cracking of the C2-C3 and C1-O bonds in the pyran ring, and the oxidation of hydroxyl group in cellulose molecules, respectively. Subsequently, the effect of PDs on the surface topography of the pressboard was examined. The results showed that the surface roughness of the pressboard changed with a "U-shaped" trend under the influence of PDs, first decreasing and then increasing immediately after. In addition, "micro pits" were found on the surface of the pressboard. Breakdown of the pressboard happened when a micro pit grew to a critical depth.

A system consisting of a plano-convex mirror and reflecting surfaces of Vertical Cavity Surface-Emitting Laser (VCSEL) Strip Array of Diode Lasers has been calculated and proved to have a self-reproducing ray sink in it. The initial positions and slopes of two representative groups of light rays are set, and the position and slope of each light ray at each Distributed Bragg Reflector (DBR) of Diode lasers are obtained by computation. The system is a folded resonator, every VCSEL is connected by the axis of the resonator, and this axis is formed by linking the correspondent reflective points on the inner spherical surface of the mirror and the reflective points on the Bragg mirrors. One approach could be to fabricate the array directly on a plane of a GaAs (or Si) plano-convex mirror. The resonator can contain many VCSELs, and therefore can afford a high quality laser beam and high-power output.

An effective solving method is presented to study influences of foam filler on axially crushing characteristics of fiber-reinforced tapered square metal tubes based on axial collapse models of foam-filled metal square tubes and finite element calculation of foam-filled tapered composite square tubes. By means of finite element calculation, an influenced factor [Formula: see text] is introduced in the solving process. Comparing results from experiment and finite element calculation, the feasibility of the present analytical method is validated. The effects of basic angle of composite tapered square tube, foam filler, fiber-reinforced orientation, thickness ratio between metal wall and fiber layer and loading speed on axially crushing characteristics of foam-filled fiber-reinforced composite tapered square tubes are studied.

An X-ray focusing monochromator is proposed, which is composed of an X-ray source, a highly oriented pyrolytic graphite and two poly-capillary X-ray lenses. Through the function of the front poly-capillary X-ray lens, the X-ray beams diffracted by the highly oriented pyrolytic graphite changed from a linear pattern with high divergence in the vertical direction, to a circular pattern with low divergence, and more X-rays are diffracted than the conventional monochromator of combining an X-ray source with a flat crystal. The post poly-capillary X-ray lens can focus the diffracted X-ray beams with low divergence into a small focal spot with high gain in power density. The results show that the gains of circular apertures with diameters of 320 and 100 μm are 12 and 22, respectively, at a distance of 221.5 mm away from the center of the highly oriented pyrolytic graphite.

The purpose of this study was to compare the condylar positional changes after bilateral sagittal split ramus osteotomy (BSSRO) in patients with mandibular retrusion and those with mandibular prognathism. We also studied the correlation between the degree of matching of the condyle and fossa, and condylar displacement. Thirty patients with mandibular retrusion (n=11) or mandibular prognathism (n=19) who underwent BSSRO were included. The condylar position was assessed from spiral computed tomographic (CT) scans taken preoperatively, during the first postoperative week, and at least 6 months postoperatively. All data were measured by MIMICS 17.0 and analyzed by Student's t test and Pearson's correlation analysis. The size of the condyles of patients with mandibular retrusion was significantly less than those of patients with mandibular prognathism (491.5 (172.8) compared with 823.2 (212.0) mm3). The size of the glenoid fossa in those with mandibular retrusion (599.6 (110.4) mm3) and those with prognathism (597.6 (151.6) mm3) did not seem to differ. Postoperatively the condyles moved outwards, backwards, and downwards in both groups of patients. Correlation analysis between the condyle:fossa volume ratio and the condylar positional changes showed that a large condyle:fossa volume ratio correlated with the smaller positional changes in the condyle. The condylar position changed immediately after mandibular advancement and setback, and persisted in the long term. Larger condyles tended to have fewer positional changes.

Our aim was to evaluate the possible correlation between maternal alcohol consumption during the first trimester and the risk of having an offspring with non-syndromic oral cleft. We electronically searched all published papers from 1950 to 2019 about maternal alcohol consumption and oral clefts in PubMed, the Cochrane Central Register of Controlled Trials (CENTRAL), and the Institute for Scientific Information (ISI) databases. Descriptive and quantitative data were extracted from eligible studies for systemic evaluation and meta-analysis. A total of 12 publications met our inclusion criteria, and nine of them presented sufficient data for quantitative analyses. The overall odds ratio of the nine reports was 1.00 (95% CI 0.87 to 1.15) for cleft lip with or without cleft palate (CL/P) and 1.02 (95% CI 0.92 to 1.14) for cleft palate only, indicating no significant difference between drinking and non-drinking mothers in the risk of having a child with a non-syndromic oral cleft. We found no confirmatory evidence for the presence of a dose-response relation between alcohol consumption and increase in the risk of oral cleft. Nevertheless, four of the studies enrolled found significantly increased risk of CL/P among mothers in the groups that consumed the most alcohol. All but one of the four studies suggested a positive correlation between binge drinking and the occurrence of non-syndromic oral cleft. Although we found no concrete correlation between mild alcohol consumption during pregnancy and the occurrence of non-syndromic oral cleft, precautions should still be taken to avoid binge drinking during the first trimester.

Intensity distribution of the X-ray beam redirected through a conventional monolithic poly-capillary quasi-parallel lens is similar to a Gaussian distribution, which will bring about unsatisfactory imaging quality for medical applications and affect the peak-to-background ratio in X-ray diffraction experiments. These disadvantages can be overcome by adopting poly-capillary X-ray lenses structured with three tiers that fabricated from different diameters of capillaries. This paper developed a mathematical model of monolithic poly-capillary quasi-parallel lens composed with different diameter tubes, and experimental data of intensity distribution, transmission efficiency and divergence have been compared with simulation results based on a ray-tracing technique.

Two samples of ancient Chinese coins were analyzed with a confocal three-dimensional micro-X-ray fluoroscope. The depth distributions of elemental iron (Fe), calcium (Ca) and copper (Cu) were obtained based on this non-destructive measurement method. One coin, named “Chongning Tongbao”, was certified as genuine in accordance with the available archaeological data, whereas another coin, named “Zhenglong Yuanbao”, was identified as a reproduction.

We know of no universally accepted classification for intracapsular condylar fractures. We propose here a new classification based on the concept of a "disc-condyle" unit, and validate the classification based on outcomes of treatment. From 1 January 2010 - 31 December 2014, 55 patients with unilateral intracapsular condylar fractures were classified into three types: type A has no reduction in mandibular height or displacement of the disc (n=7); type B has displacement of the disc with no reduction in mandibular height (n=17); and type C has reduced mandibular height with or without displacement of the disc (n=31). We treated types B and C by open reduction and fixation, while type A fractures were managed non-surgically. At six month follow-up, we found no significant differences in the vertical height of the ramus, mandibular deviation, protrusion, or lateral protrusion between the fractured and healthy sides. All patients had normal occlusion postoperatively and only one patient (type C) reported pain. Magnetic resonance imaging and computed tomography showed good osseous healing and disc-condylar relations in all cases. Our results show that this new classification of intracapsular condylar fractures is a safe and easy way to obtain satisfactory outcomes of treatment. However, it needs further independent validation.

Ellipsoidal monocapillary x-ray optics are used as condenser lenses in full-field transmission x-ray microscopy. The numerical aperture (NA) of the ellipsoidal monocapillary is designed to match that of the x-ray zone plate objective. In practice, monocapillaries have inner-surface errors that lead to mismatches between the monocapillary and the zone plate. In this study, mathematical models of monocapillaries with elliptic cross-section deformation and centreline straightness errors were developed, respectively. Furthermore, the optical properties of these monocapillaries were simulated based on a ray-tracing method. The simulation provides a qualitative picture of the NA and illumination angle distributions of the ellipsoidal monocapillary with inner-surface errors, and it is useful for predicting the inner-surface imperfections from the x-ray ring behind the monocapillary.

A folded resonator of vertical cavity surface-emitting (VCSE) stripe array of diode lasers is presented. The upper surfaces of VCSELs (vertical cavity surface emitting lasers) are anti-reflected, and the lower surfaces are Bragg mirrors. A strip plane-convex mirror and the Bragg mirrors are applied to form the folded resonator. This strip plane have some transparent partitions. Every VCSEL is connected by the axis of the resonator, and this axis is formed by linking the correspondent reflective points on the inner spherical surface of the mirror and the reflective points on the Bragg mirrors. One approach could be to fabricate the array directly on a plane of a GaAs (or Si) plano-convex mirror. The resonator is also a spatial filter, and can contain many VCSELs, and therefore can afford a high quality laser beam and high-power output.

A micro X-ray fluorescence setup was presented, based on an ellipsoidal capillary and a traditional laboratorial X-ray source. Using Ray-tracing principle, we have simulated the transmission path of X-ray beam in the ellipsoidal capillary and designed the optimal parameters of the ellipsoidal capillary for the micro X-ray fluorescence setup. We demonstrate that ellipsoidal capillary is well suited as condenser for the micro X-ray fluorescence based on traditional laboratorial X-ray source. Furthermore, we obtain the 2D mapping image of the leaf blade sample by using the ellipsoidal capillary we designed.

Three-dimensional (3D) confocal x-ray fluorescence analysis technology is widely used, but the quantitative analysis of elemental spatial distributions of solid samples is complicated. This paper explores a quantitative analysis method that can be applied to solid samples. Fluorescence spectra of liquid samples are obtained on a 3D confocal x-ray fluorescence spectrometer. Curves are plotted showing the relationships between the fluorescence count intensity and the mass percentage of metal ions, and the respective fitting-curve equations are determined according to the curve morphology. Fluorescence intensity as a function of the mass percentage and depth position is derived from the samples for a particular acquisition time. These data play a potential role in the subsequent quantitative analysis of unknown mass percentages of solid samples.

A new type of x-ray lens composed of multi-square polycapillary slices (ASPXRL) used in focusing parallel x-ray beam was presented in this paper. Compared with conventional x-ray polycapillary lens, ASPXRL can provide smaller and brighter focus. The effects of the manufacturing imperfections on focusing quality of ASPXRL were evaluated with the values of transmission efficiency and discussed. It is suggested that ASPXRL has application prospects as a condenser lens for x-ray microscopy and flux collectors for x-ray analytical instruments.

The properties of standard Laguerre–Gaussian beam (sLGB) and elegant Laguerre–Gaussian beam (eLGB) through the misaligned complex hard edge apertures (MCHEAs) are investigated. Analytical formulae for the far field distributions of sLGBs and eLGBs through the different hard edge apertures are derived based on the generalized Huygens–Fresnel diffraction integral equation. The propagation properties and beam qualities of sLGBs and eLGBs are studied comparatively. It is shown that the divergence angle of sLGBs with the low order modes is less than that of eLGBs. However, the energy distributions of eLGBs with the high order modes after through the multiple hard edged apertures are more convergent in comparison with sLGBs, and eLGBs have the better beam quality than sLGBs. The study results are useful for the propagations and applications of sLGBs and eLGBs through the complex optical systems.

Using misalignment matrix of optical components, the change law of the single-pass diffraction loss with the discharge tube and resonator mirror misalignment of two-dimensional axisymmetric-fold combination cavity CO 2 laser are researched and analyzed. The change curves with misalignment angle are also calculated and simulated numerically in this paper. The results show that when the laser parameters are ascertained, the single-pass diffraction loss is less than 0.1, the misalignment angle range of discharge tube and resonator mirror are obtained, and it is beneficial to the adoption of resonator and instruction for installation.

Despite better reconstruction quality for incomplete or noisy projection data compared to analytic reconstruction, computed tomography iterative techniques are time-consuming, mainly due to high system matrix computation. A polar-coordinate pixel model with concentric annuluses of different radial widths was established and a fast method for computing the system matrix was presented based on characteristics of this model. Compared with the Siddon algorithm and an efficient Cartesian algorithm introduced by Zhang, the proposed algorithm based on the simultaneous algebraic reconstruction technique shows speed advantages for both numerical simulation and experiment, without noticeable loss of image quality.

Due to the finite size of detector unit, the area integral model (AIM) is closer to reality than the line integral model (LIM) when X-ray beams passing through a sample cast to CCD. A simultaneous algebraic reconstruction technique (SART) algorithm for AIM is proposed for improved image quality. First, a cone-beam to parallel-beam rearranged step was performed to simplify the model computation. Then, a judgement formula was used to quickly find the cells to be traversed by a strip-shaped X-ray beam and an effective method was presented to calculate intersection region. Via the comparison, both simulation and experiment show that this area-based SART has better reconstruction quality than traditional line-based SART. The algorithm is demonstrated the ability to micro-CT reconstruction. This AIM approach could be adapted for other iterative algorithms in fan-beam or small cone- angle beam CT geometry.

A method based on the single-bounce ellipsoidal monocapillary X-ray condenser (SEGMXC) was improved for determining the focal spot size of the high-energy microfocal X-ray source. HfO2 was selected as the high-density material (∼9.68g/cm3) and coated on the inner surface of the SEGMXC by the atomic layer deposition method. The focal spot size of a microfocal spot X-ray source was obtained as 33.14 ± 0.02 μm and the relative deviation of the effective size given by the manufacturer was 5.3%.

The non-uniformities of a fabricated mono-capillary X-ray lens (MCXRL) degrade the performance of the X-ray analysis system. The main evaluation criterion of a fabricated MCXRL is total root mean square error, which consists of the profile error (PE) and the central axis straightness error (CASE). In the present paper, we develop an open-source code package to evaluate the PE value of varying diameter glass tubes (VDGT). The source code named ‘PSO X-ray Lens Finder’ in the package is written using the particle swarm optimization (PSO) algorithm, and the other source code named ‘MMN X-ray Lens Finder’ is developed using the multiparameter multilevel nested-loop (MMN) algorithm. We take the research of a paraboloidal MCXRL as an example to introduce the source code package, and the mathematical theory and calculation details of the package are given in the method section. As a result, the ‘MMN X-ray Lens Finder’ can be used alone to guide engineers in cutting a high-performance MCXRL from VDGT; the ‘PSO X-ray Lens Finder’ can be applied as a faster alternative strategy for cutting work.

Non-tradition-employed (NTE) lenses are presented. The characters are proved by the experiment. Multilayer reflection coatings on designated zones on the surfaces of the lens are different in reflectivity(R) because of different NTE aims. Incident light beams paraxially bounce back and forth between two surfaces of the lens, then leave from a zone or multiple zones of the lens. The application schemes involve solid-state multiple-pass cell, combination of light beams or laser beams, and phase-locking of a laser array.

The line deviations and angle deviations of the injected beam at the resonator mirrors in the large area discharge CO2 laser (LADCL) are changed when the output mirror and the phase-locking mirror (PLM) are misaligned. The equiphase surfaces excited by the injected beam are different in the laser resonator and the effect of phase-locking will be influenced. It is shown that the misalignment of PLM is the main cause of phase-locking range reduction. The misalignment of the output mirror will mainly result in the deviation of the output beam, and the misalignment of the PLM will mainly cause decrease of the light intensity. And the maximum misaligned angle should not exceed 20 s in order to obtain the ideal effect of phase-locking. The calculated results can provide references for studying deeply the misalignment of LADCL.

A polycapillary X-ray optics is developed and used in a micro-area XRD residual stress measurement. The results are compared with the traditional pinhole method. Both diffraction intensity and peak height obtained from the application of this polycapillary are enhanced by dozens of times than that from the pinhole method. The experimental results exhibit the advantage of this polycapillary optics in the micro-area residual stress measurement with higher detectable signal and more accuracy.

Injury to the mandibular condyle in children usually leads to malocclusion and disharmony of facial growth. Our aim was to study the facial growth after reconstruction of the mandibular condyle using autogenous coronoid process grafts in children with unilateral ankylosis of the temporomandibular joint (TMJ). We followed up 10 growing patients with unilateral bony ankylosis of the TMJ who had been admitted to the West China Hospital of Stomatology, Sichuan University (Chengdu, China) between 1 January 2008 and 31 December 2012. There were three boys and seven girls, age range 5–12 years at the time of operation. In each case, patients were treated by gap arthroplasty, reconstruction of the condyle with an ipsilateral coronoid process, and interposition of the pedicled temporalis fascial flap during one operation. The mean (range) postoperative follow up was 4.73 (3–6) years. Postoperative panoramic radiographs were taken, and the growth of the mandibular height and length on the affected side was measured and compared with the healthy side. All patients had an uneventful, normal recovery. The mean (range) maximal mouth opening at the end of follow up was 35.6 (32–41) mm. Both the height of the ramus and the length of the mandible continued to grow after successful treatment of the ankylosis (using autogenous coronoid process grafts for reconstruction of the condyle) but the deficit in growth was not completely made up. The final height of the ramus on the affected side (at the end of follow up) had increased by 25% (p = 0.012) and the final length of the mandible on the affected side by 26% (p = 0.010) compared with immediately after operation. For comparison of the rate of growth, the increased height of the ramus of the affected side was 47% lower (p = 0.003), while the increased length of the mandible on the affected side was 27% shorter (p = 0.008) compared with the healthy side. The mandible on the affected side continued to grow after successful treatment of the ankylosis, but the growth deficit was not made up completely. The rate of growth of the affected mandible seemed to be less than on the undisturbed side even after treatment of the ankylosis.

A conic glass monocapillary was developed and used at the Biological Macromolecules Station (BMS) in Beijing Synchrotron Radiation Facility (BSRF). The structure and transmission property of this optics is reported here in details. The experiments have shown that the value of full width at the half maximum (FWHM) of the X-ray beams transmitted through this optics was nearly unchanged within a short distance. This is very convenient for further measurement of samples. The power diffraction experiments of CeO2 revealed that the Debye rings are much clearer in the case of applying this optics. The ratio of error in the diffraction peak position is reduced significantly to the value as less as 0.042%. (C) 2014 Elsevier B.V. All rights reserved

A new type of tapered single capillary X-ray lens, which is manufactured by using the nesting method, is proposed to generate a small focal spot with high power density gain for micro X-ray analysis. Experimentally, it was found that the nested tapered single capillary has a good geometric shape, and the tubes nest well. The experimental results verify that the nested manufacture process is feasible. Moreover, the transmission performance of the nested tapered single capillary was measured in the laboratory. At a distance 1.5 mm from the exit of the nested tapered single capillary, a beam spot of 9.1 μ m was obtained. The transmission efficiency of the nested tapered single capillary was 55%, and the gain in power density measured with or without the nested tapered single capillary was 16.

A new stripe-shaped lens laser scheme is proposed. The Nd 3 + : g l a s s concave-convex lens with a diameter of 110 mm and thickness of 10 mm is processed, which the curvature radius of concave surface is 10,000 mm and the curvature radius of convex surface is 9800 mm. The reflectivity at the rest of the two surfaces is 99.9%, except that the transmission is 15% at the central circular area of the concave having a diameter of 8 mm to 1.06 µm light wave. The stripe-shaped area of the lens is pumped with a pulsed Xenon flashlamp which the diameter is 8 mm, and the energy of 521 mJ single transverse mode at 1.06 µm laser is obtained from the central regions of the concave surface, and the feasibility of the lens laser scheme is verified.

The confocal X-ray diffraction (XRD) technology based on a polycapillary slightly focusing X-ray lens (PSFXRL) in excitation channel and a polycapillary parallel X-ray lens (PPXRL) with a long input focal distance in detection channel was developed. The output focal spot of the PSFXRL and the input focal spot of the PPXRL were adjusted in confocal configuration, and only the X-rays from the volume overlapped by these foci could be accordingly detected. This confocal configuration was helpful in decreasing background. The convergence of the beam focused by the PSFXRL and divergence of the beam which could be collected by the PPXRL with a long input focal distance were both about 9 mrad at 8 keV. This was helpful in improving the resolution of lattice spacing of this confocal XRD technology. The gain in power density of such PSFXRL and PPXRL was about 120 and 7 at 11 keV, respectively, which was helpful in using the low power source to perform XRD analysis efficiently. The performances of this confocal XRD technology were provided, and some common plastics were analyzed. The experimental results demonstrated that the confocal diffraction technology base on polycapillary slightly focusing X-ray optics had wide potential applications.

In combination with a single-crystal diamond anvil cell (DAC), a polycapillary half-lens (PHL) re-focusing optics has been used to perform high-pressure extended X-ray absorption fine-structure measurements. It is found that a large divergent X-ray beam induced by the PHL leads the Bragg glitches from single-crystal diamond to be broadened significantly and the intensity of the glitches to be reduced strongly so that most of the DAC glitches are efficiently suppressed. The remaining glitches can be easily removed by rotating the DAC by a few degrees with respect to the X-ray beam. Accurate X-ray absorption fine-structure (XAFS) spectra of polycrystalline Ge powder with a glitch-free energy range from -200 to 800 eV relative to the Ge absorption edge are obtained using this method at high pressures up to 23.7 GPa, demonstrating the capability of PHL optics in eliminating the DAC glitches for high-pressure XAFS experiments. This approach brings new possibilities to perform XAFS measurements using a DAC up to ultrahigh pressures.

The effect of human parathyroid hormone 1-34 (PTH) and zoledronic acid (ZA) alone or in combination on bone healing in osteoporotic settings was tested using implants inserted in tibiae of ovariectomized (OVX) rats. Combination therapy promoted bone healing more than each treatment alone 12 weeks after implant insertion. PTH and ZA have been demonstrated to be effective on implant fixation. However, reports about the combined use of PTH and ZA for promotion of bone healing around implant in osteoporotic settings are still limited. This study aims to investigate effects of PTH+ZA on implant stabilization in OVX rats. Twelve weeks after bilateral ovariectomy, OVX rats randomly received implants without or with ZA (by immersion in 1 mg/ml ZA solution for 24 h). Subsequently, half of the animals from each group also received subcutaneous injections of PTH (60 μg/kg, three times a week) for 12 weeks. Thus, there were four groups: control, PTH, ZA, and PTH+ZA. All treatments promoted bone healing around implant compared to control, but PTH+ZA treatment showed significantly stronger effects than PTH or ZA alone in histological, micro-CT, and biomechanical tests. The results indicated the additive effects of PTH and ZA on implant fixation in OVX rats; it was suggested that the anabolic effect of PTH was potent and not blunted by ZA during bone healing around implant when used concurrently.

A new type of axisymmetric-fold-combination CO2 laser, which is constituted by several axisymmetric four-mirror cavities, is studied theoretically in this paper. The mutual energy coupling occurring within the communal discharge region of the unstable resonator to inject seed signals into each sub-resonator is demonstrated by theoretical deduction. The numerical results have proved that phase-locking could be achieved in this cavity, and the beams with phase-locking have both a higher intensity and a smaller light spot than the ones without phase-locking.

In order to study the thermal optical effect (TOE) resulting from the axisymmetrical sources of thermal energy at the output mirror of CO2 laser, the Heat Conduction Poisson Equation (HCPE) has been solved in the output mirror. Then the temperature distribution is given. The temperature variations will cause the surface distortion and the phase shift at the output mirror. Therefore, the output laser beam will be subject to thermal optical distortion and phase change. The numerical examples are to confirm our calculated results.

A laboratory confocal micro X-ray fluorescence (micro-XRF) spectrometer based on a polycapillary focusing X-ray lens (PFXRL) in the excitation channel and a polycapillary parallel X-ray lens (PPXRL) in the detection channel was used to carry out the size-resolved source apportionment of aerosol particles. The PPXRL in the detection channel both increased the collection angle of the detector and improved the signal-to-noise ratio of the X-ray spectrum. When this confocal micro-XRF spectrometer was used to carry out the quantitative XRF analysis of single aerosol particles with smaller size than that of the overlapping foci of the PFXRL and the PPXRL, the sensitivity was corrected by using a Gaussian function. The size-resolved “fingerprint database” for the air pollution sources was established based on the quantitative XRF results for single aerosol particles. The size-resolved aerosol particles on hazy-foggy days in Beijing were apportioned.

The divergence of the beam focused by polycapillary X-ray optics (PXRO) varied at different distances from the exit of the PXRO. This distance dependence of the divergence of the PXRO was defined as the fine structures of the divergence of the PXRO. The fine structures of the divergence of the PXRO were presented in order to use them fully. There were main three types of the PXRO, such as polycapillary parallel X-ray lens (PPXRL), polycapillary focusing X-ray lens (PFXRL) and polycapillary slightly focusing X-ray lens (PSFXRL). For the PPXRL, the divergence decreased near its exit. The reason for this might be that the divergence near the exit of the PPXRL depended mainly on the X-rays traversing directly through the monocapillaries in the center of the PPXRL without total reflection. For the PFXRL and PSFXRL, they both had respectively a focal depth over which the beam sizes at different output distances remained acceptably small. For the 8 keV X-rays, the focal depth and divergence over the focal depth of the PFXRL were about 300 μm and 25.0 mrad, respectively. At the same energy of 8 keV, the focal depth and divergence over the focal depth of the PSFXRL were about 500 μm and 12.5 mrad, respectively. The divergence of the PFXRL and the PSFXRL depended mainly on the angles between axes of monocapillaries that composed them.

Ovariectomized (OVX) rats with tibial fracture received vehicle, ZA, PTH, or ZA plus PTH treatment for 4 and 8 weeks. Bone metabolism, callus formation, and the mass of undisturbed bone tissue were evaluated by serum analysis, histology, immunohistochemistry, radiography, micro-computerized tomography, and biomechanical test. Previous studies have demonstrated the effect of ZA or PTH on osteoporotic fracture healing. However, reports about effects of ZA plus PTH on callus formation of osteoporotic fracture were limited. This study was designed to investigate the impact of combined treatment with ZA and PTH on fracture healing in OVX rats. Twelve weeks after bilateral ovariectomy, all rats underwent unilateral transverse osteotomy on tibiae. Animals then randomly received vehicle, ZA (1.5 μg/kg weekly), PTH (60 μg/kg, three times a week), or ZA plus PTH until death at 4 and 8 weeks. The blood and bilateral tibiae of rats were harvested for evaluation. All treatments increased callus formation and strength other than the control; ZA + PTH showed the strongest effects on percent bone volume (BV/TV), trabecular thickness, total fluorescence-marked callus area, and biomechanical strength. Additionally, inhibited RANKL and enhanced osteoprotegerin expression were observed in the ZA + PTH group. But no difference in bone mineral density and BV/TV of the contralateral tibiae was observed between treated groups. Findings in this study suggested an additive effect of ZA and PTH on fracture healing in OVX rats, and this additive effect was specific to callus formation, not to undisturbed bone tissue.

The influences of misalignments of an axisymmetrical folded-combined (ASFC) CO2 laser on the output power are studied in detail. The new cavity axes are established by using the misaligned matrixes corresponding to the misalignments of the output mirror and the discharge tube, and the diffraction losses of the cavity and the output powers are calculated. It is shown that the influences of the misalignments on the output power are significant when the misalignment angle of the output mirror exceeds 20 s. These calculated values afford references for the design of ASFC CO2 lasers.

A method of reflection-injection phase-locking used on two-dimensional axisymmetric-fold combination resonator (ASFC) CO2 laser has been proposed. The structure characteristics and the method of phase-locking have been introduced. The expression of output light intensity distribution has been deduced by matrix theory and Collins Formula and the output light intensity distribution has been numerically calculated and simulated. Comparing the output light intensity distribution in the case of phase-locking with that of non-phase-locking. The result shows that this method of phase-locking greatly improve the characteristics of output beam.