A strategy for the preparation of super-hydrophilic molybdenum disulfide composites applied to remove uranium from wastewater.

Due to the radioactivity of uranium, the discharged nuclear wastewater not only causes certain damage to the ecology, but also causes certain harm to human life and health. Adsorption is considered to be one of the most effective ways to remove uranium. In this paper, a kind of MoS2 adsorbent was prepared by the solid phase synthesis method and functionalized with NiCo-LDH. The raw materials of MoS2 are cheap and easy to obtain, and the preparation conditions are simple, and large quantities can be obtained without limitations. MoS2 functionalized with NiCo-LDH provides more adsorption sites for the adsorbent and at the same time improves the hydrophilicity of the adsorbent, so that the active sites can fully combine with uranyl ions. The maximum adsorption capacity of the Langmuir isothermal adsorption model is 492.83 mg g-1. The selective adsorption capacity of uranium can reach 76.12% in the multi-ion coexistence system. By analyzing the adsorption mechanism with FT-IR and XRD, it is believed that on the one hand, UO22+ forms a covalent bond with Mo in MoS2 and coordinates with S on the surface of MoS2. On the other hand, UO22+ enters the NiCo-LDH layer for ion exchange with NO3- and coordinates with -OH on the surface of NiCo-LDH. The successful preparation of the MoS2/NiCo-LDH composite provides a certain application prospect for the uranium adsorption field.

Solar engineering of wastewater treatment for full mineralization of organic pollutants.

Full mineralization of organic pollutants is a tough task with existing technologies. Even if all conventional energies and extremes are exhausted, high-temperature wastewater treatment is not worth the loss from the perspective of energy. Solar engineering holds promise for the full mineralization of organic pollutants to tackle the global fossil energy shortage. Here, we report solar engineering for full mineralization and efficient solar utilization. The solar energies and spectrum were fully utilized to initiate the solar heat and solar electricity. Two energies were applied to trigger the thermochemical and electrochemical oxidation of the organic pollutants. Our study bridges the gap between the energy and environment towards efficient solar utilization and effective water treatment. As a proof-of-concept study, this demonstrates a solar engineering of full phenol mineralization in wastewater. A record phenol mineralization rate was achieved to reach an oxidation rate of 98% and COD of 93% under a constant current density of 50mA/cm2 at 150°C. UV and HPLC were used to detect the intermediate products during variable time intervals. The results showed that the intermediate products are composed of maleic acid, hydroquinone and p-benzoquinone. In the extreme high temperature (90°C), the solar oxidation time and pathway are greatly altered. The reaction rate constant at 150°C is about 11 times than that at 90°C. More solar heat significantly reduces the activated energy of the pollutant oxidation and lowers the potential of electrolysis.

WiPg: Contactless Action Recognition Using Ambient Wi-Fi Signals.

Motion recognition has a wide range of applications at present. Recently, motion recognition by analyzing the channel state information (CSI) in Wi-Fi packets has been favored by more and more scholars. Because CSI collected in the wireless signal environment of human activity usually carries a large amount of human-related information, the motion-recognition model trained for a specific person usually does not work well in predicting another person's motion. To deal with the difference, we propose a personnel-independent action-recognition model called WiPg, which is built by convolutional neural network (CNN) and generative adversarial network (GAN). According to CSI data of 14 yoga movements of 10 experimenters with different body types, model training and testing were carried out, and the recognition results, independent of bod type, were obtained. The experimental results show that the average correct rate of WiPg can reach 92.7% for recognition of the 14 yoga poses, and WiPg realizes "cross-personnel" movement recognition with excellent recognition performance.

Facile Deflagration Synthesis of Hollow Carbon Nanospheres with Efficient Performance for Solar Water Evaporation.

Solar water evaporation is a promising and environment-friendly approach to relieve global water scarcity issues. Currently, many reports show that the voids and porous structure are beneficial to the absorption of solar energy to generate water steam. Herein, carbon nanospheres with central cavity structures are rationally designed by the one-step NaN3/fluorinated graphite deflagration method. The Na clusters derived from NaN3 deflagration are not only provided as the hollow templates but also react with fluorinated graphite to release heat, further boosting the formation of hollow carbon nanospheres (HCSs). Benefiting from the diversity of carbon nanomaterials, rough surface, unique hollow structures, and numerous micron/submicron holes, the light absorption ability, heat localization, and water supply capacity of HCSs have been significantly enhanced. Because of these advantages, the HCS-3 exhibits an excellent water evaporation efficiency of 92.7% at 1 kW m-2, which is much higher than that of carbon nanospheres, graphene oxide, and even most of the previous carbon materials. In addition, we demonstrated that the HCSs have a long-term stability and high efficiency of production of drinkable water and purifying various types of wastewater, including seawater, strong acid/alkaline water, and water containing dyes. To sum up, the deflagration synthetic technology as a facile and ultrafast process can be a new insight for future photothermal material design.

Comparison study of carbon clusters formation during thermal decomposition of 1,3,5-triamino-2,4,6-trinitrobenzene and benzotrifuroxan: a ReaxFF based sequential molecular dynamics simulation.

Carbon rich clusters are usually found after the detonation of explosives, which greatly hinder their further decomposition into small molecules. A comparison study of thermal decomposition and clusters formation between 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) and benzotrifuroxan (BTF) crystals was conducted to uncover the mechanisms behind their distinct differences in sensitivity and reaction violence, which has not been investigated in detail. The simulations of heating at 3500 K, then expansion and cooling were conducted through reactive molecular dynamics using the ReaxFF-lg force field. As a result, the initial low decay rate indicates that TATB is more stable than BTF under high temperatures, while once ignited it decays faster than BTF. Nevertheless, BTF decomposes more completely with a higher potential energy release, a greater amount of final products, and higher reaction frequencies, and shows higher reaction violence than TATB. More and heavier clusters occur in TATB crystals compared with those in BTF. Large clusters form during the heating process and then partly dissociate during expansion and cooling. A faster cooling rate facilitates larger clusters formation. Graphitic geometries as well as carbon rings and carbon chains are common in the stable clusters. Besides, further simulations show that a lower heating temperature facilitates larger clusters formation both in TATB and BTF. Our results are expected to deepen the insight into the mechanisms of carbon clusters formation and the different performances of TATB and BTF.

The solid phase thermal decomposition and nanocrystal effect of hexahydro-1,3,5-trinitro-1,3,5-triazine (RDX) via ReaxFF large-scale molecular dynamics simulation.

The solid phase thermal decomposition and nanocrystal effect are extremely important to understand the ignition, combustion, reaction growth and buildup to detonation under shock wave action. To explore the basic mechanism at the atomic level and understand the interaction among nanocrystal lattices, molecules, and intermediates during the solid phase decomposition, ReaxFF large-scale molecular dynamics simulation at 1000-3000 K was demonstrated on the solid phase of nanocrystalline RDX with a size in the range of 5-12 nm. Based on the analysis of the RDX decay and chemical species, we found that the whole decomposition process can be divided into the solid-affected stage and the following less-condensed phase stage. From the results of NO2 diffusion and high frequency reaction statistics for the nanocrystal effect on the RDX decay, intermediate diffusion was found to be strongly associated with the chemical pathway. In addition, it was found for the first time that the thermal decomposition of RDX originates from the inside of the nanocrystal instead of its surface. Furthermore, a promising uniform energy distribution mechanism transfer by vibration inside the nanocrystalline RDX was demonstrated. The detailed information derived from this study can aid in the thorough understanding of the size effect on the chemical kinetics of nanoexplosives, especially for thermal decomposition and reaction growth.

Laser-Ignited Relay-Domino-Like Reactions in Graphene Oxide/CL-20 Films for High-Temperature Pulse Preparation of Bi-Layered Photothermal Membranes.

Light-ignited combustions have been proposed for a variety of industrial and scientific applications. They suffer, however, from ultrahigh light ignition thresholds and poor self-propagating combustion of typical high-energy density materials, e.g., 2,4,6,8,10,12-(hexanitrohexaaza)cyclododecane (CL-20). Here, reported is that both light ignition and combustion performance of CL-20 are greatly enhanced by embedding ε-CL-20 particles in a graphene oxide (GO) matrix. The GO matrix yields a drastic temperature rise that is sufficient to trigger the combustion of GO/CL-20 under low laser irradiation (35.6 mJ) with only 6 wt% of GO. The domino-like reduction-combustion of the GO matrix can serve as a relay and deliver the decomposition-combustion of CL-20 to its neighbor sites, forming a relay-domino-like reaction. In particular, a synergistic reaction between GO and CL-20 occurrs, facilitating more energy release of the GO/CL-20 composite. The novel relay-domino-like reaction coupled with the synergistic reaction of CL-20 and GO results in a deflagration of the material, which generates a high-temperature pulse (HTP) that can be guided to produce advanced functional materials. As a proof of concept, a bi-layered photothermal membrane is prepared by HTP treatment in an extremely simple and fast way, which can serve as a model architecture for efficient interfacial water evaporation.

Enhanced Thermal Decomposition Properties of CL-20 through Space-Confining in Three-Dimensional Hierarchically Ordered Porous Carbon.

High energy and low signature properties are the future trend of solid propellant development. As a new and promising oxidizer, hexanitrohexaazaisowurtzitane (CL-20) is expected to replace the conventional oxidizer ammonium perchlorate to reach above goals. However, the high pressure exponent of CL-20 hinders its application in solid propellants so that the development of effective catalysts to improve the thermal decomposition properties of CL-20 still remains challenging. Here, 3D hierarchically ordered porous carbon (3D HOPC) is presented as a catalyst for the thermal decomposition of CL-20 via synthesizing a series of nanostructured CL-20/HOPC composites. In these nanocomposites, CL-20 is homogeneously space-confined into the 3D HOPC scaffold as nanocrystals 9.2-26.5 nm in diameter. The effect of the pore textural parameters and surface modification of 3D HOPC as well as CL-20 loading amount on the thermal decomposition of CL-20 is discussed. A significant improvement of the thermal decomposition properties of CL-20 is achieved with remarkable decrease in decomposition peak temperature (from 247.0 to 174.8 °C) and activation energy (from 165.5 to 115.3 kJ/mol). The exceptional performance of 3D HOPC could be attributed to its well-connected 3D hierarchically ordered porous structure, high surface area, and the confined CL-20 nanocrystals. This work clearly demonstrates that 3D HOPC is a superior catalyst for CL-20 thermal decomposition and opens new potential for further applications of CL-20 in solid propellants.

Core-Shell Al-Polytetrafluoroethylene (PTFE) Configurations to Enhance Reaction Kinetics and Energy Performance for Nanoenergetic Materials.

The energy performance of solid energetic materials (Al, Mg, etc.) is typically restricted by a natural passivation layer and the diffusion-limited kinetics between the oxidizer and the metal. In this work, we use polytetrafluoroethylene (PTFE) as the fluorine carrier and the shielding layer to construct a new type of nano-Al based fuels. The PTFE shell not only prevents nano-Al layers from oxidation, but also assists in enhancing the reaction kinetics, greatly improving the stability and reactivity of fuels. An in situ chemical vapor deposition combined with the electrical explosion of wires (EEW) method is used to fabricate core-shell nanostructures. Studies show that by controlling the stoichiometric ratio of the precursors, the morphology of the PTFE shell and the energy performance can be easily tuned. The resultant composites exhibit superior energy output characters than that of their physically mixed Al/PTFE counterparts. This synthetic strategy might provide a general approach to prepare other high-energy fuels (Mg, Si).

Facile fabrication of porous CL-20 for low sensitivity high explosives.

A facile solvent/non-solvent co-crystallization technology is applied to fabricate porous CL-20, which exhibits interesting morphologies and low sensitivity with ß-cyclodextrin as a crystal modifier.

[Dynamic monitoring on ovarian function among patients having had cervical squamous cell carcinoma transposition surgery].

UNLABELLED: To investigate the changes in ovarian function and the radiotherapeutic influence on ovarian function on patients with cervical squamous cell carcinoma. METHODS: We retrospectively analyzed 53 cases of cervical cancer patients FIGO staging I B1- II B who had received ovarian transposition surgery at the Maternal and Child Health Hospital of Jiangxi province from January 2009 to June 2012. All the patients included in the study were FIGO staging I B1- II B and had undergone radiation therapy, including 38 staging I B1- II A2 cervical cancer patients receiving chemo-therapy after radical radiotherapy due to the presence of risk factors and other 15 patients with stage II B to radical concurrent chemoradiotherapy ovarian transposition. Ovarian transposition methods would include laparoscopic ovarian transposition and transabdominal ovarian transposition. 15 concurrent patients with stage II B who currently receiving chemo-radiotherapy were under laparoscopic ovarian transposition. Among the 38 radical hysterectomy patients, 31 were having abdominal ovarian transposition, and the remaining 7 cases were laparoscopic. All the 53 patients had undergone radiotherapy. The levels of serum female hormones FSH, LH, E2 were determined to monitor the ovarian endocrine function. RESULTS: According to FIGO staging, 18 cases were stage I B1, 15 cases I B2, 3 cases II A1, 2 cases II A2 and 15 cases II B. Patients' age range was from 28 to 44 years old, with an average of 37.7 years, median age as 38 years. 14 patients (63.6%) were still normal ovarian function after radiotherapy by laparoscopic ovarian transposition, which was 100.0% before radiotherapy. There was a significant difference (P < 0.05)compared with before radiotherapy. After transabdominal ovarian transposition surgery and radiotherapy, normal ovarian function 22 cases (71.0%), and there was a significant difference (P < 0.05) compared with before radiotherapy. No significant difference was found with regard to the proportion of normal ovarian function after radiotherapy between the two groups of patients with laparoscopic and transabdominal ovarian transposition (P > 0.05). CONCLUSION: For the young cervical cancer patients, even with ovarian transposition, ovarian dysfunction was still evident after radiotherapy. There was no significant difference between laparoscopic and transabdominal ovarian transposition.

A novel preparation method for drug nanocrystals and characterization by ultrasonic spray-assisted electrostatic adsorption.

PURPOSE: The purpose of this study was to develop a novel and continuous method for preparing a nanosized particle of drug crystals and to characterize its properties. MATERIALS AND METHODS: A new apparatus was introduced to crystallize nanosized drug crystals of amitriptyline hydrochloride as a model drug. The samples were prepared in the pure state by ultrasonic spray, and elaborated deposition was completed via electrostatic adsorption. Scanning electron microscopy, X-ray powder diffraction, and atomic force microscopy were used to characterize the size of the particles; this was subsequently followed by differential scanning calorimetry. RESULTS AND DISCUSSION: Nanoparticles of drug crystals were successfully prepared. The size of the drug crystals ranged from 20 nm to 400 nm; the particle size of amitriptyline hydrochloride was approximately 71 nm. The particles were spherical and rectangular in shape. Moreover, the melting point of the nanoparticles decreased from 198.2°C to 196.3°C when compared to raw particle crystals. Furthermore, the agglomeration effect was also attenuated as a result of electrostatic repulsion among each particle when absorbed, and depositing on the inner wall of the gathering unit occurred under the electrostatic effect. CONCLUSION: Ultrasonic spray-assisted electrostatic adsorption is a very effective and continuous method to produce drug nanocrystals. This method can be applied to poorly water-soluble drugs, and it can also be a very effective alternative for industrial production. Once the working parameters are given, drug nanocrystals will be produced continuously.

Fabrication of FOX-7 quasi-three-dimensional grids of one-dimensional nanostructures via a spray freeze-drying technique and size-dependence of thermal properties.

1,1-Diamino-2,2-dinitroethylene (C(2)H(4)N(4)O(4), FOX-7) quasi-three-dimensional (3D) grids, a promising high-energy-density material with superior sensitivity properties, were synthesized by a spray freeze-drying technique. The FOX-7 3D grids were constructed from one-dimensional nanostructures. The sizes and structures of the FOX-7 3D grids strongly depend on the concentration of the aqueous solution of FOX-7. A possible formation mechanism of this structure was proposed in detail. Thermal analysis reveals that decrease in average particle sizes of FOX-7 grids results in a lower decomposition temperature and a much higher decomposition rate, which is in agreement with those reported about inorganic nanomaterials.

[Study on the value assessment of various screening programs regarding cervical cancer screening strategy in the rural areas of China].

OBJECTIVE: To evaluate the application value and feasibility of various cervical screening methods and to explore a rapid and efficient cervical cancer screening program for the women in the rural areas of China. METHODS: We sequentially conducted human papillomavirus (HPV) DNA test by hybrid capture-2 (hc2) with cervical cells, liquid-based thinprep cytology test (TCT), visual inspection with acetic acid (VIA), visual inspection with iodine (VILI), colposcopy respectively for the 2499 married women between 30 and 49 years from Xiushui county of Jiangxi province. All the detection methods were performed independently under double-blind design. Women who were diagnosed positive for having any VIA,VILI and colposcopy inspection or for those women who were diagnosed negative for VIA, VILI and colposcopy but with positive result of HPV or TCT test underwent cervical biopsy directly and endocervical curettage (ECC)when necessary. We performed cervical biopsy endocervical curettage within two weeks to observe the sensitive (SE), specificity (SP), negative predict value (NPV) and positive predict value (PPV) of these detection methods when used alone or combined each other, including HPV test, TCT inspection, VIA, VILI, and colposcopy, the pathological diagnosises of cervical tissue were confirmed by IARC (International Agency for Research on Cancer) while the cytological findings were underegone through the updated program of TBS (The Bethesda System) in 2001. RESULTS: A total of 2499 women underwent the screening and found 443 women who were diagnosed as HPV positive, 337 women with abnormal cervical cytology and 27 women with ASC-H, 157 cases with ASCUS; 103 cases with HSIL, 49 cases with LSIL and 1 cervical cancer. According to the pathological findings. There were 181 women diagnosed as cervical intraepithelial neoplasia (CIN) or cervical cancer, including 81 cases with CIN1 37 cases with CIN2,60 case cervical cancer. The sensitivity rates of HPV, TCT, HPV+ TCT, VIA, VILI, VIA+VILI and colposcopy were 96.67%, 89.47%, 97.98%, 56.57%, 36.36%, 63.64% and 39.39%, and the specificity rates were 85.00%, 96.91%, 86.97%, 94.60%, 96.23%, 92.97% and 98.14% respectively. CONCLUSION: HPV + TCT seemed to be more sensitive than other screening methods in the cervical cancer screening program.