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An approach to differentially modify the internal surface of porous silicon nanoparticles (pSiNPs) with hydrophobic dodecene and the external surface with antifouling poly

The hydrogenation and co-hydrogenation behaviors of Hami coal and Tahe residue were investigated in an autoclave, and the feasible technical route for co-hydrogenation was explored. The experimental results showed that Hami coal had good hydroliquefaction performance and the suitable reaction temperature was 445°C. At 445°C and 9 MPa, the coal conversion rate reached 98.74%, and the oil yield reached 68.54%. The hydrogenation tests of Tahe residue showed obvious coking tendency at the lower temperature, and it was difficult to achieve lightening. At 430°C, the conversion rate of Tahe residue was only 66.38%, the light oil yield was only 50.01%, and its coking rate was as high as 9.45%. The coking rate increased with the reaction temperature. When the mixtures of Hami coal and Tahe residue were co-hydrogenated directly, the conversion rate of the raw materials was lower, and the coke phenomenon was obvious. At the coal/oil ratio was 40/60, the conversion rate was 97.79%, and oil yield was 73.36%. Adding hydrogen solvents into the co-hydrogenation system could effectively inhibit coke formation, increase the conversion rate, and lighten co-hydrogenation products. When the amount of coal was 45% and Tahe residue was 20%, the conversion rate of raw materials was 98.38% and the oil yield was 74.82%.

Metal-organic frameworks (MOFs) have been a focus of research because of their unique porous structure, but they are usually not directly for electrocatalysis. Herein, we prepared a special class of Fe/Zn/Mo-based trimetallic hybrid zeolitic imidazolate frameworks by in situ solvothermal synthesis that have the potential to act directly as highly efficient oxygen evolution reaction electrocatalysts. This work provides a foundation for the preparation of multimetal MOFs and expands the investigation of electrocatalysts.

A series of digermylenes R(EGeL)

Objective: Notch1 is an important receptor in Notch signaling pathway. Abnormal Notch1 expression or function is associated with the pathogenesis of OA. There is evidence that the abnormal expression of miR-9 is related to the pathogenesis of OA. Bioinformatics analysis showed that there was a targeting relationship between miR-9 and Notch1’s 3′-UTR, suggesting that there might be a mutual regulation between them. In this study, we established an OA rat model to investigate whether miR-9 plays a role in regulating Notch1 expression, affecting cartilage matrix degradation and chondrocyte apoptosis in OA. Methods: OA model rats were divided into three groups: OA group, OA + agomir group, OA + miR-9 agomir group. The content of Hyp in articular fluid was measured by ELISA, the activity of caspase-3 was detected by kit, the mRNA expressions of miR-9, COL2A1, Notch1 and Hes5 was detected by qRT-PCR, and the protein expressions of Notch1 and Hes5 in articular cartilage was detected by Western blot. Chondrocytes were separated into control group, IL-1β +miR-NC group, IL-1β +miR-9 mimic group followed by analysis of mRNA expressions of miR-9, COL2A1, Notch1 and Hes5 were detected by qRT-PCR, protein expressions of Notch1 and Hes5 by Western blot, and cell apoptosis by flow cytometry. Results: Compared with Sham group, the levels of IL-1β , Hyp, Notch1, Hes5 and Caspase-3 in the synovial fluid of rats in OA group were increased significantly, while the mRNA expressions of miR-9, COL2A1 and Notch1 and Hes5 level in cartilage tissue were decreased significantly. Intra-articular injection of miR-9 agomir could significantly reduce the content of Hyp, the mRNA expressions of Notch1 and Hes5 and the activity of caspase-3 in cartilage tissue of OA rats, increase the mRNA expressions of miR-9 and COL2A1, and decrease the protein expressions of Notch1 and Hes5. After treated with IL-1β , the expressions of Notch1 and Hes5 were increased, the mRNA expressions of miR-9 and COL2A1 were decreased, and apoptosis of chondrocyte was increased in chondrocyte. After miR-9 mimic transfection, miR-9 and COL2A1 mRNA expressions were increased, Notch1 and Hes5 expressions were decreased, and apoptosis of chondrocyte was decreased under IL-1β treatment. Conclusion: Reduced miR-9 expression upregulates Notch1 expression and promotes the pathogenesis of OA. Increased miR-9 expression can inhibit Notch1 expression, reduce cartilage matrix degradation and inhibit chondrocyte apoptosis.

Herein, a Co(II) heteroatom metal-organic framework was successfully post-modified via unsaturated coordinated S precisely capturing Ni2+ on the surface of the porous structure. The newly pristine bimetallic MOFs have increasing active edge sites (Ni(II) and S), boosting electrocatalytic activity toward oxygen evolution reaction and hydrogen evolution reaction.

The optimal L2-L∞ control problem of a class of uncertain stochastic systems with Wiener process disturbances is studied. Based on the robust L2-L∞ control theory, it gives a sufficient con...

To evaluate the clinical outcome of tibiotalocalcaneal fusion using cannulated screw and humeral proximal locking plate inverted fixation through a lateral transfibular approach.From June 2015 to December 2018, 15 patients underwent a tibiotalocalcaneal fusion operation using cannulated screw and inverted proximal humerus locking plate through a transfibular approach. There were 10 males and 5 females with the age ranging from 45 to 72 (58.9±6.1) years, and the course of disease ranged from 2 to 35 (11.9±7.9)years. Preoperative diagnosis included 8 cases of post traumatic arthritis, 2 cases of Charcot arthritis, 2 cases of Charcot-Marie -Tooth (CMT), 1 case of ankle tuberculosis, 1 case of talar necrosis, and 1 case of pigmented villonnodular synovitis. Among them, 8 patients were combined with simple varus deformity, 4 patients with simple valgus deformity, 2 patients with equinovarus deformity, 1 patient with equinovarus deformity, 2 patients with adduction and internal rotation of middle and forefoot. American Orthopaedic Foot and Ankle Society (AOFAS) ankle and hindfoot score and the visual analogue scale (VAS) score were used to evaluate the clinical outcome at the last follow up.One lost follow up and remaining fourteen patients were followed up. The follow up time ranged from 10 to 25(16.6±4.3) months. All the 15 patients had primary healing. Fusion time ranged from 15 to 24 (16.8 ± 2.4) weeks after operation. One patient with diabetes experienced delayed union and was successfully treated with secondary bone grafting combined with Platelet-Rich Plasma (PRP) injection. The AOFAS score increased from 38.7±3.3 to 84.5±2.6 (Tibiotalocalcaneal fusion used cannulated screw and humeral proximal locking plate inverted fixation through a lateral transfibular approach has the advantages of relatively simple technique, high fusion rate, especially for patients with posterior foot deformity, which has satisfactory short term effects.

Porous silicon (pSi) nanomaterials are increasingly attractive for biomedical applications due to their promising properties such as simple and feasible fabrication procedures, tunable morphology, versatile surface modification routes, biocompatibility and biodegradability. This review focuses on recent advances in surface modification of pSi for controlled drug delivery applications. A range of functionalization strategies and fabrication methods for pSi-polymer hybrids are summarized. Surface engineering solutions such as stimuli-responsive polymer grafting, stealth coatings and active targeting modifications are highlighted as examples to demonstrate what can be achieved. Finally, the current status of engineered pSi nanomaterials for in vivo applications is reviewed and future prospects and challenges in drug-delivery applications are discussed.

In order to eliminate the Nuclear Overhause Effect (NOE) of carbon nucleus in 13 C CP/MAS/TOSS NMR experiment and to obtain more accurate carbon structure parameters, NOE intensities of different model compounds were examined. The results show that there is an obvious carbon structure error between the fitting test value and theoretical one for different model compounds. The aliphatic carbon error is 25%–125%, while the aromatic carbon is 4%–50%. Therefore, the nonlinear regression equation is obtained by regression analysis of the measured and theoretical values of aliphatic and aromatic carbon in model compounds. Moreover, this equation was used to calibrate the carbon structure of 9,10-dimethylanthracene. It is found that after calibration the error between measured and theoretical value for aliphatic is reduced from 119.60% to 7.84%. The error for aromatic carbon is reduced from −17.10% to 1.11%. And the error is within 10%. Then, the carbon structural parameters of different coals are calibrated by the regression equation. Compared with elements analysis, H/C error is 45%–53%, while the calibration error is only 4%–13%, which is consistent with the results of elemental analysis after calibration. It indicates that the nonlinear regression equation could easily and precisely eliminate the solid state NMR carbon nucleus NOE and also provide new technical support for carbon structure analysis in coal.

We report a facile approach to prepare metal-nanocatalyst-incorporated carbon thin films with uniform size distribution via carbonization of surface-mounted metal-organic frameworks (SURMOFs) and metal oxo-clusters loaded SURMOF. The calcinated thin films have high performance of methylene blue degradation and the reduction of nitrobenzene. This study describes a general strategy for preparing various nanoparticle-impregnated porous carbon thin films for applications in catalysis.

Plant leaf diseases are closely related to people's daily life. Due to the wide variety of diseases, it is not only time-consuming and labor-intensive to identify and classify diseases by artificial eyes, but also easy to be misidentified with having a high error rate. Therefore, we proposed a deep learning-based method to identify and classify plant leaf diseases. The proposed method can take the advantages of the neural network to extract the characteristics of diseased parts, and thus to classify target disease areas. To address the issues of long training convergence time and too-large model parameters, the traditional convolutional neural network was improved by combining a structure of inception module, a squeeze-and-excitation (SE) module and a global pooling layer to identify diseases. Through the Inception structure, the feature data of the convolutional layer were fused in multi-scales to improve the accuracy on the leaf disease dataset. Finally, the global average pooling layer was used instead of the fully connected layer to reduce the number of model parameters. Compared with some traditional convolutional neural networks, our model yielded better performance and achieved an accuracy of 91.7% on the test data set. At the same time, the number of model parameters and training time have also been greatly reduced. The experimental classification on plant leaf diseases indicated that our method is feasible and effective.

Apple tree disease is a main threat factor to apple quality and yield. This paper proposed an improved convolutional neural network model to classify apple tree diseases. It took the advantages of neural network to extract the deep characteristics of disease parts, and used deep learning to classify target disease areas. In order to improve the classification accuracy and speed up the convergence of the network model, the center loss and focal loss functions were fused, instead of the traditional softmax loss function, which was especially important for our classification network model. Experimental results on our apple trunk dataset showed that our model achieved an accuracy of 94.5%. Therefore our method is feasible and effective for apple tree disease identification.

Pyrolysis experiments were carried out in a tubular furnace. The characteristics of pyrolysis tar were analyzed by GC/MS. The results indicated that the aliphatic hydrocarbon yield derived from co-pyrolysis tar of cotton stalk and Shenmu coal was obviously higher than that of Shenmu coal pyrolysis under optimum condition. Moreover, microcrystalline cellulose was selected as a model compound and the co-pyrolysis tar of microcrystalline cellulose and Shenmu coal was analyzed for comparison. Base on the experimental results, it was indicated that the alkyl radicals generated from pyrolysis were converted to aliphatic hydrocarbons by radical reactions. Furthermore, the mechanisms of aliphatic hydrocarbon formation were discussed during co-pyrolysis of cotton stalk and Shenmu coal.

A novel isohedral 3-periodic net (i.e. a net with one kind of tile), showing a Cairo pentagonal tiling projection on the Euclidean plane, has been identified in a series of site-modified CuCN/CuSCN networks, namely, [Cu6 (SCN)2 (CN)6 ⋅Ni(tpy)2 ]n (1), [Cu6 (SCN)(CN)7 ⋅Ni(tpy)2 ]n (2) and [Cu6 (CN)8 ⋅Ni(tpy)2 ]n (3) (tpy=2,2':6'',2''-terpyridine). These infinite inclusion compounds were prepared via a solvothermal sulfur migration reaction with subtle modification to fine-tune the sulfur content. The chiroptical activity of single crystals, which arises from the intrinsically chiral net, was confirmed by X-ray diffraction and solid-state circular dichroism spectra.

An amine-functionalized Cd(II) boron imidazolate framework (BIF-77) with three-dimensional open structure has been successfully synthesized, which can load Ag nanoparticles (NPs) for photocatalytic degradation of methylene blue (MB).

Two low-dimensional Cu(I) boron imidazolate frameworks (BIFs), [CuBH(bim)3]n (BIF-40; bim = benzimidazolate) and [CuBH(im)3]n (BIF-6, im = imidazolate), have been synthesized and both of them display unique mechanochromism. In addition, BIF-40 showed reducing activity due to the rich B–H bonds in the structure, and it was employed to load AuPd bimetal nanoparticles through a one-step process for further catalysis. The corresponding mechanism involving a grinding process between chains or layers is discussed in detail. This work not only provides compelling evidence for designing and applying coordination polymers as mechanochromic materials, but also develops an eco-friendly strategy for loading bimetallic NPs into BIFs.

A functional Cu(I) boron imidazolate framework (BIF) with a ladder-chain structure can not only change to another single-chain structure by incorporating 4,4'-bipyridine, but can also act as a reducing agent to load trimetal Au-Ag-Pd nanoparticles directly; the BIF with loaded noble NPs showed an excellent reduction effect on 4-nitrophenol. Moreover, we obtained a porous borocarbonitride by the direct carbonisation of this low-dimensional BIF. The resulting porous borocarbonitride exhibits fast adsorption behavior for 4-nitrophenol and can be a high-temperature conductor.

In a general face recognition scenario, classifications attend to assign a label to a single probe image. So far a branch of classification methods, which assume that a probe image tends to lie on the same class-specific subspace as the gallery images from the same class, have drawn wide attention for their good performance. Actually, those linear regression based classifications are sufficient to achieve promising recognition accuracy. However if there are wide ranges of variations on probe images such as pixel noises, lighting variant, they could deviate the probe images from their correct locations in feature space. To solve this problem, we propose a new linear regression based method by generating an extended set for a probe image. In the first step of our method, we not only produce the low dimension features for a probe but also generate virtual samples by adding randomness into downsampling. The second step is to classify the probe by using canonical correlation analysis. As the generated virtual probe samples have high possibility to cover the correct location in feature space, our proposed method shows promising performance in the experiments.

To study the synthetic strategy from cages to extended frameworks is very important to elucidate and mimic cage-based self-assembly behavior in zeolites and other open frameworks. Here, two dodecahedral cages are rationally designed by using tridentate boron imidazolate ligands to link tetrahedral or square metal centers. The self-assembly of metal boron imidazolate cages is successfully realized. The cage-based materials display good properties on gas adsorption and reducing noble metals. This work may help us to understand the formation mechanism of extended metal–organic frameworks.

Tetrolets are Haar-type wavelets whose supports are tetrominoes which are shapes made by connecting four equal-sized squares. Firstly, the magnitude of polarization image and angle of polarization image can be decomposed into low-frequency coefficients and high-frequency coefficients with multi-scales and multi-directions using tetrolet transform. For the low-frequency coefficients, the average fusion method is used. For the each directional high frequency sub-band coefficients, the larger value of region energy information measurement is used to select the better coefficients for fusion. At last the fused image can be obtained by utilizing inverse transform for fused tetrolet coefficients. Experimental results show that the proposed method can detect image features more effectively and the fused image has better subjective visual effect.

The contourlet transform is a new two-dimensional extension of the wavelet transform using multiscale and directional filter banks and has better approximation precision and better sparse description. Firstly, the magnitude of polarization image and angle of polarization image can be decomposed into low-frequency coefficients and high-frequency coefficients with multi-scales and multi-directions using the contourlet transform. For the low-frequency coefficients, the average fusion method is used. For the each directional high frequency sub-band coefficients, the larger value of region teager energy information measurement is used to select the better coefficients for fusion. At last the fused image can be obtained by utilizing inverse transform for fused contourlet coefficients. Experimental results show that the proposed algorithm works better in preserving the edges and texture information compared with the traditional image fusion algorithms.

Culture is necessary for modern university system reflected on three aspects as the relationship between university and culture, system and culture, modern university system and culture. The organization properties of university determine their establishment must follow cultural logic. On one hand, the properties of university in academic organization enable it to put forward requirements on via value culture and behavioral culture, on the other hand, the social organization properties from university also influence the modern university system in the forms of local culture, university culture and subject culture. In addition, the cultural distributions of different stakeholders in university organization also provide analysis thought for modern university system establishment.

This paper tries to study the issues related to private higher education in China, such as students, teachers, teaching method and so on. According to the successful experience of other countries, advanced school-running concept plays a key role in the construction of high-level private universities. It is the core and soul of school development. This paper raises new school-running concept from such aspects: developing school centering on humans, enjoying unique advantages and high teaching quality.

Kidney-replenishing herb is a traditional medicine formula in China which has been widely used for clinical treatment of recurrent miscarriage. Our previous study showed that Kidney-replenishing herb could promote proliferation and inhibit apoptosis of the human first-trimester trophoblasts. In the present study, we further explored the potential mechanism and signal pathway of Kidney-replenishing herb on human trophoblast cells. Our research showed that Kidney-replenishing herb stimulated proliferation and reduced apoptosis of human trophoblast cells in vitro, and this appeared to be positive correlation with SOCS-3 transcription, suggesting that Kidney-replenishing herb regulated biological functions of human trophoblast cells by inducing SCOS-3 expression. Furthermore, the Kidney-replenishing herb treatment stimulated the phosphorylation of ERK1/2, and blocking the signaling pathway by mitogen-activated protein MAPK (MEK) inhibitor, U0126, inhibited Kidney-replenishing herb-induced SOCS-3 transcription, depressed proliferation, and promoted apoptosis of human trophoblasts. Kidney-replenishing herbs still induced ERK1/2 phosphorylation after SOCS-3 siRNA silence. Overexpression of SOCS-3 stimulated the proliferation of trophoblast. These findings suggest that SOCS-3 expression is induced by Kidney-replenishing herbs via activation of MAPK pathways, and this may possibly be involved in promoting human trophoblast cells growth which is contributed to embryo development.

This paper presents a method for robot path planning based on ant colony optimization algorithm, in order to resolve the weakness of ant colony algorithm such as slow convergence rate and easy to fall into local optimum and traps. This method uses anti-potential field to make the robot escape from them smoothly, and at the end of each cycle, uses the way of judge first and then hybridization to optimize the algorithm. Finally, the simulation results show that the performance of the algorithm has been improved, and proved that the optimization algorithm is valid and feasible.

Speech enhancement is crucial for speech recognition accuracy. How to eliminate the effect of the noise constitutes a challenging problem in speech processing. This paper presents a new technique for speech enhancement in a noisy environment based on the empirical mode decomposition (EMD) algorithm and wavelet threshold. With the EMD, the noise speech signals can be decomposed into a sum of the band-limited function called intrinsic mode functions (IMFs), which is a zero-mean AM-FM component. Then wavelet threshold of the IMF components can be used to eliminate the effect of the noise for speech enhancement. Experimental results show that the proposed speech enhancement by de-noising algorithm is possible to achieve an excellent balance between suppresses noise effectively and preserves as many target characteristics of original signal as possible.

Non-subsampled contourlet transform (NSCT) is the combination of the multi-scale analysis and multi-directional analysis in processing high-dimensional signals and has better approximation precision and better sparse description. A novel and efficient fusion method of infrared image and visible image based on NSCT is proposed. Firstly, source fusion images can be decomposed into low-frequency coefficients and high-frequency coefficients using the NSCT. For the low-frequency coefficients, the average fusion algorithm is used. For the each directional high frequency sub-band coefficients, the larger value and region average gradient maximum criterion is used to select the better coefficients for fusion. Experimental results show that the proposed algorithm can achieve better result compared with the traditional image fusion algorithms.

The coffee flavor compounds acquire a significant place in the improving the flavor of cigarette. In the present paper, the support vector machine is used to develop quantitative relationships between the retention time and four molecular descriptors of 52 compounds. The model of support vector machine gives good statistical results compared to those give by multiple linear regressions and support vector machine. The contribution of each descriptor to structure-retention time relationships was evaluated. It indicates the importance of the atoms number and type of parameter. The proposed method can be successfully used to predict the retention time with only four molecular descriptors which can be calculated directly from molecular structure alone.

To build intelligent library service, a platform for data analysis is essential. In this paper, we are trying to build a platform, and to study possible application of such a Big-Data platform.

A series of 3D neutral boron imidazolate frameworks (BIFs) with octahedral metal centers were synthesized based on the charge-balancing principle. Au-Pd nanoparticles (NPs) with a mean size of 2.12 nm were then successfully obtained and encapsulated in these BIF structures through the simultaneous reduction of Au(3+)/Pd(3+) ions by B-H bonds of tridentate boron ligands. The very small sizes of these Au-Pd NPs are attributed to the pore confinement effect of BIFs. This work not only brings new methodology for the construction of neutral BIFs but also suggests a new strategy for loading smaller-sized bimetallic NPs into BIFs.

A cubic cationic cage is rationally designed by using tridentate boron-imidazolate ligands to link tetrahedral metal Zn(ii) centers, which displays excellent properties in the Cr2O72− exchange and can reduce Au3+ ions into Au nanoparticles directly.

The stationary contourlet transform is built upon nonsubsampled pyramids and nonsubsampled directional filter banks and provides a shift invariant directional multiresolution image representation. Firstly, several SAR images can be decomposed into low-frequency coefficients and high-frequency coefficients with multi-scales and multi-directions using the stationary contourlet transform. For the low-frequency coefficients, the average fusion method is used. For the each directional high frequency sub-band coefficients, the larger value of horizontal and vertical direction gradient information measurement is used to select the better coefficients for fusion. At last the fused image can be obtained by utilizing inverse transform for fused contourlet coefficients. Experimental results show that the proposed algorithm gives more satisfactory results than the traditional image fusion algorithms in preserving the edges and texture information.

A new approach for speech stream detection based on empirical mode decomposition (EMD) under a noisy environment is proposed. Accurate speech stream detection proves to significantly improve speech recognition performance under noise. The proposed algorithm relies on the Teager energy and spectral entropy characteristics of the signal to determine whether an input frame is speech or non-speech. Firstly, the noise signals can be decomposed into different numbers of sub-signals called intrinsic mode functions (IMFs) with the EMD. Then, spectral entropy is used to extract the desired feature for noisy IMF components and Teager energy is used to non-noisy IMF components. Finally, in order to show the effectiveness of the proposed method, we present examples showing that the new measure is more effective than traditional measures. The experiments show that the proposed algorithm can suppress different noise types with different SNR.

In order to accomplish tracking of moving objects requirements, and overcome the defect of occlusion in the process of tracking moving object, this paper presents a method which uses a combination of MeanShift and Kalman filter algorithm. MeanShift object tracking algorithm uses a histogram to describe the color characteristics of an object, and search the location of an image region that the color histogram is closest to the histogram of the object. Histogram similarity is defined in terms of the Bhattacharya coefficient. When the moving object is a large area blocked, the future state of moving object is estimated by Kalman filter. Experimental results verify that the proposed algorithm achieves efficient tracking of moving objects under the confusing situations.

This paper describes the design of a two-dimensional photoelectric detector, in which silicon photovoltaic cells are used as photoelectric receiver, and laser signal is converted into electrical signals. The weak electrical signals can be amplified by the high power low noise with variable magnification amplifier controlled by single-chip microcontroller PIC. Then using the variable attenuator MAX521 complete selectable attenuation for the analog signal. The detector is able to adapt for high-precision detection of the laser light source in the case of changes in the strength of the near and far distances and light. The practicality and detection performance of the receiver can be ensured. This two-dimensional photoelectric detector is particularly applicable to the construction site where are special requirements for some installation accuracy, which can be a good solution to the problem of excessive error of the traditional installation process.

A novel and efficient speckle noise reduction algorithm based on wavelet transform by cycle spinning for removing speckle of unknown variance and minimizing the effect of pseudo-Gibbs phenomena from Synthetic Aperture Radar (SAR) images is proposed. Therefore, we show that the sub-band decompositions of logarithmically transformed SAR images. Then, we process and reconstruct multi-resolution wavelet coefficients by wavelet-threshold using cycle spinning, a technique estimating the true images as the linear average of individual estimates derived from wavelet thresholded translated versions of the noise images. Experimental results show that the proposed de-noising algorithm is possible to achieve an excellent balance between suppresses speckle effectively and weaken as many image Gibbs phenomena as possible. Quantitative and qualitative comparisons of the results obtained by the new method with the results achieved from the other speckle noise reduction techniques demonstrate its higher performance for speckle reduction in SAR images.

We present the formation of the largest titanium-oxo cluster, [Ti42(μ3-O)60(OiPr)42(OH)12)](6-), with the first fullerene-like Ti-O shell structure. The {Ti42O60} core of this compound exemplifies the same icosahedral (Ih) symmetry as C60, the highest possible symmetry for molecules. According to the coordination environments, the Ti centers in this cluster can be arranged into a Platonic {Ti12} icosahedron and an Archimedean {Ti30} icosidodecahedron. The solution stability of this cluster was confirmed by electrospray ionization mass spectrometry. The spherical body of the {Ti42O60} core has an inside diameter of 1.05 nm and an outside diameter of 1.53 nm, which could be directly visualized by high-resolution transmission electron microscopy. Our results demonstrate that titanium oxide can also form fullerene-like shell structures.

Accurate endpoint detection is crucial for speech recognition accuracy. A novel approach that finds robust features for endpoint detection based on the empirical mode decomposition (EMD) algorithm and spectral entropy in a noisy environment is proposed. With the EMD, the noise signals can be decomposed into different numbers of sub-signals called intrinsic mode functions (IMFs), which is a zero-mean AM-FM component. Then spectral entropy can be used to extract the desired feature for IMF components. In order to show the effectiveness of the proposed method, we present examples showing that the new measure is more effective than traditional measures. The experiments show that the proposed algorithm can suppress different noise types with different SNR, and the algorithm is robust in the real signal tests.