Adsorption thermodynamics and kinetics of nanomaterials: theory and experimental insight into nano-effect.

Nanomaterials have excellent adsorption performance due to nano-effect and have been widely used in many fields. The adsorption performance of nanomaterials depends on their adsorption thermodynamics and kinetics. Here, the thermodynamic and kinetic equations of adsorption for spherical nanoparticles are first derived in theory. The mechanisms and regularities of influences of nano-effect on thermodynamics and kinetics, using nano-CdS adsorption of methylene blue as a probe, were investigated. The results show that there are significant influences of nano-effect (i.e., interface area effect and interface tension effect) on the thermodynamics and kinetics of nanoparticle adsorption. When the particle radius is larger and beyond the nanometer scale (∼100 nm), the nano-effect can be neglected. When the radius of the nanoparticle is within 10-50 nm, the nano-effect of adsorption is mainly the interface area effect. When the radius is less than 10 nm, the influences of both the interface area effect and the interface tension effect on adsorption thermodynamics and kinetics become more significant. The theoretic equations and experimental insights in the present work could provide a significant basis and reference for improving and perfecting the adsorption theory involving nanomaterials and provide guidelines for the explanations of adsorption mechanisms as well as the selection of adsorbents.

Trajectory-BERT: Trajectory Estimation Based on BERT Trajectory Pre-Training Model and Particle Filter Algorithm.

In the realm of aviation, trajectory data play a crucial role in determining the target's flight intentions and guaranteeing flight safety. However, the data collection process can be hindered by noise or signal interruptions, thus diminishing the precision of the data. This paper uses the bidirectional encoder representations from transformers (BERT) model to solve the problem by masking the high-precision automatic dependent survey broadcast (ADS-B) trajectory data and estimating the mask position value based on the front and rear trajectory points during BERT model training. Through this process, the model acquires knowledge of intricate motion patterns within the trajectory data and acquires the BERT pre-training Model. Afterwards, a refined particle filter algorithm is utilized to generate alternative trajectory sets for observation trajectory data that is prone to noise. Ultimately, the BERT trajectory pre-training model is supplied with the alternative trajectory set, and the optimal trajectory is determined by computing the maximum posterior probability. The results of the experiment show that the model has good performance and is stronger than traditional algorithms.

A network system for the prevention and treatment of mushroom poisoning in Chuxiong Autonomous Prefecture, Yunnan Province, China: implementation and assessment.

BACKGROUND: Mushroom poisoning is a major public health issue in China. The integration of medical resources from different institutes of different levels is crucial in reducing the harm of mushroom poisoning. However, few studies have provided comprehensive implementation procedures and postimplementation effectiveness evaluations. To reduce the harm caused by mushroom poisoning, a network system for the prevention and treatment of mushroom poisoning (NSPTMP) was established in Chuxiong, Yunnan Province, a high-risk area for mushroom poisoning. METHODS: The NSPTMP consists of three types of institutions, namely, centers for disease prevention, hospitals, and health administration departments, with each kind of institution comprising prefecture, county/city, town, and village levels. After three years of implementation, the network was evaluated by comparing the indices before and after network implementation using data from the "Foodborne Disease Outbreak Surveillance System" and 17 hospitals in Chuxiong. The indices included the fatalities caused by mushroom poisoning, the composition ratios of different types of mushrooms for both outpatients and inpatients and the hospitalization rates. RESULTS: Compared to the average fatality rate of mushroom poisoning from 2015 to 2017, the average fatality rate from 2018 to 2020 significantly decreased from 0.57 to 0.06% (P < 0.001). Regarding the poisonous genus containing lethal mushrooms, the outpatient and inpatient composition ratios significantly decreased for Amanita (9.36-2.91% and 57.23-17.68%, respectively) and Russula (15.27-8.41%) (P < 0.05). Regarding poisonous mushrooms that caused mild symptoms, the outpatient and inpatient composition ratios significantly increased for Scleroderma (5.13-13.90% and 2.89-18.90%, respectively) and Boletaceae (19.08-31.71%) (P < 0.05), and the hospitalization rates significantly increased for Scleroderma (6.33-18.02%) and Boletaceae (5.65-12.71%) (P < 0.05). CONCLUSIONS: These findings suggest that the NSPTMP effectively reduced the harm caused by mushroom poisoning. In addition to the integration of medical resources, the development of poisonous mushroom identification, hierarchical treatment systems in hospitals, public education, and professional training also played important roles in improving the system's effectiveness. The establishment and evaluation of the NSPTMP in Chuxiong Prefecture can provide valuable insights and serve as a model for other regions facing similar challenges in managing mushroom poisoning.

Metformin inhibits EV71­induced pyroptosis by upregulating DEP domain­containing mTOR­interacting protein.

Enterovirus 71 (EV71) infection is one of the main causes of severe hand, foot and mouth disease (HFMD), which is usually accompanied by a marked inflammatory response. The excessive inflammatory response has been implicated to serve an important role in EV71-caused HFMD. Pyroptosis is a type of inflammatory programmed cell death. Therefore, a novel treatment strategy against EV71 infection could aim to alleviate the inflammatory response through inhibition of EV71-induced pyroptosis. The present study revealed that metformin had this therapeutic potential. A cell model of EV71 infection was established, cell viability was measured by CCK8 assay, cell damage was measured by LDH release kit, and the dead and dying cells were excluded by propidium iodide staining. The intracellular levels of DEP domain-containing mTOR interacting protein (DEPTOR) and pyroptosis-associated molecules were measured by western blot analysis, the NLRP3 expression was assessed by immunofluorescence labeling, and virus titers in cell culture supernatants were determined by a cell culture infectious dose 50 assay. The results demonstrated that EV71 infection could induce pyroptosis in a time- and dose-dependent manner, and metformin could inhibit EV71-induced pyroptosis. The mechanism of metformin inhibiting EV71-induced pyroptosis was explored next. Subsequent experiments indicated that metformin could increase the levels of DEPTOR, which were decreased by EV71. Finally, overexpression of DEPTOR in cells could reduce EV71-induced pyroptosis. Overall, the present study demonstrated that metformin could exert a novel pharmacodynamic anti-pyroptosis effect in the treatment of EV71 infection by upregulating DEPTOR expression.

Phase Engineering of Molybdenum Carbide/Oxide for Highly-Efficient Electrocatalytic Hydrogen Production.

Molybdenum carbide is one of non-precious metal materials and it is a promising electrocatalyst for hydrogen production. Synthesis and improvement of molybdenum carbide's catalytic performance is of great significance. Herein, carbon-based Mo2 C with hybrid phase of MoO2 was fabricated by matching the composition of Mo and C derived from pomelo peel and optimizing raw carbon amount and prolysis temperature. The resulting MoO2 /Mo2 C@C is composed of loose microspheres with mesoporous microstructure and is self-assembled from nanoparticles. The results show that MoO2 /Mo2 C@C2 material exhibits excellent HER performance and only a low overpotentials of 143 mV is needed to drive the current density of 10 mA cm-2 in alkaline solution, and Tafel slopes are only 63.4 mV dec-1 , respectively. Notably, it has potential application at low overpotentials to drive large current density and this strategy also provides a universal route to prepare non-noble metal catalyst with hybrid phase of oxide/carbide.

Constructing Netlike Nanosheets of ZnO/BiOCl with Heterojunction as Robust Material for Electrochemical Amine Detection.

The electrochemical sensing is a potential method for detection of trace toxic substance. Herein, the heterojunction of netlike ZnO/BiOCl nanosheets was constructed for the enhanced electrochemical detection of ammonia. Cyclic voltammetry and linear sweep voltammetry were used to investigate the electrochemical performance. The results show that the ZnO/BiOCl-modified electrode exhibits higher sensitivity towards ammonia compared with the ZnO and BiOCl-based electrodes, which is ascribed to band structure and fast electron transfer. The high response of 11.8 µA mM-1 and a low detection limit (LOD) of 0.25 µM are achieved. In addition, the ZnO/BiOCl material exhibits high selectivity, repeatability and stability. The better linear relationship between concentration and current (R2 =0.99) is significant for quantitative detection of ammonia, implying that netlike ZnO/BiOCl nanosheets can serve as electrochemical sensing platform for detecting toxic substance. This research provides a strategy for fabricating two-dimensional netlike materials and regulating heterojunctions used for electrochemical application.

Inhibitory effect of astragalus membranaceus injection on apoptosis and autophagy induced by enterovirus 71 / 中国生物制品学杂志

@#Objective To investigate the effect of astragalus membranaceus（AM）injection on apoptosis and autophagy of human gastric epithelial cell line（GES⁃1）induced by enterovirus 71（EV71）. Methods GES⁃1 cells were cultured in vitro and divided into infected group（EV71 infected at a MOI of 3 and control group（no virus infected）. The morpho⁃logical changes of EV71 infected cells were observed by inverted microscope. The level of VP1 in GES⁃1 cells infected with EV71 was detected by Western blot；CCK⁃8 assay was used to detect the viability of GES⁃1 cells infected with EV71；Nuclear staining with DAPI was used to observe the morphological changes of nuclear apoptosis infected with EV71. GES⁃1 cells were divided into control group（without virus infection），infection group and AM intervention group with final concentration of 1，2. 5，5 and 10 μg／mL，respectively. Western blot was used to detect the effect of AM intervention on the expression of apoptosis⁃related proteins Caspase⁃3，PARP and autophagy⁃related proteins LC3 and P62 in GES⁃1 cells infected withEV71. CCK⁃8 method was used to detect the effect of AM intervention on the viability of GES⁃1 cells infected with EV71. Results GES⁃1 cells were round，shrunken with nuclear pyknosis and uneven size；VP1 level increased（t = 41. 56，P < 0. 01），cell viability decreased（t = 19. 07，P < 0. 01），Caspase⁃3 and PARP proteins were cut off（t = 35. 29 and 3. 648， P < 0. 01 and 0. 021 8，respectively），LC3Ⅱ／LC3Ⅰ ratio increased（t = 10. 16，P = 0. 000 5）and P62 protein was degraded（t = 68. 68，P < 0. 01）；AM inhibited the degradation of Caspase⁃3，PARP and P62 proteins induced by EV71 （t = 52. 66，59. 60 and 40. 22，respectively，each P < 0. 01）and increased the ratio of LC3Ⅱ／LC3Ⅰ（t = 5. 521，P = 0. 005 3），andreducedtheinhibitoryeffectofEV71ontheviabilityofGES⁃1cells（t =4. 420，P =0. 0115）. Conclusion EV71 infection induced apoptosis of GES⁃ 1 cells and AM intervention inhibited EV71 induced apoptosis by inhibiting EV71 induced autophagy.

A double-J stent misguided by zebra guidewire into ileum: A case report and literature review.

The case is a 70-year-old man who underwent a left nephroureterectomy and cutaneous ureterostomy on the contralateral side for invasive bladder cancer had to be accepted replacement of the double-J stent because of stomal stenosis.When replacing the double-J stent, a severe complication that the double-J stent misguided into the ileum occurred. The patient underwent gastrointestinal motility drugs, and the double-J stent was excreted with the feces after 12 hours. Unfortunately，patient suffered a uretero-ileal fistula and died of septic shock finally.The diagnosis and management of Uretero-ileal fistula as an iatrogenic complication of zebra guidewire use is discussed.

Transurethral Incision of the Bladder Neck at Three Points with a Needle-Type Electrode for Bladder Neck Contracture.

Purpose: This study aims to evaluate the efficacy of transurethral incision of the bladder neck (TUIBN) at three points with a needle-type electrode for treatment of bladder neck contracture (BNC). Materials and Methods: Between January 2016 and April 2021, the bladder necks of 53 patients with BNC after surgery were incised by the needle-type electrode at the 5, 7, and 12 O'clock positions. Patient's preoperational characteristics, peri- and postsurgical outcomes, such as time of operation, postoperative bladder irrigation, and postoperative hospital stay, and data of the international prostate symptom score (IPSS), maximum flow rate (Qmax), and postvoid residual (PVR) were recorded 3 and 6 months after surgery. Results: All 53 cases of BNC were successfully treated in 35.00 (25.00, 45.00) min with 18.00 (14.00, 21.00) h for postoperative bladder irrigation with little intraoperative bleeding (less than 50 mL). The postoperative hospital stay ranged from 2 to 8 days, a mean of 3.50 (3.00, 5.00) days. No major intraoperative or postoperative complications were observed. All cases that underwent follow-up assessment at 3 and 6 months after the surgery showed significantly decreased IPSS and PVR and increased Qmax compared to preoperation ones (p ≤ 0.001). Of these 53 patients, there was no recurrence in severe BNC patients, but 5 of 53 (9.4%) BNC patients developed BNC again within 6 months and required repeated TUIBN. Thirty patients comprised five recurrent cases with a follow-up period of more than 1 year. Conclusions: TUIBN at three points provides a safe, effective, and reliable option in treating patients with BNC.

Total astragalosides decrease apoptosis and pyroptosis by inhibiting enterovirus 71 replication in gastric epithelial cells.

Enterovirus 71 (EV71) is one of the primary pathogens involved in severe hand, foot and mouth disease in children. EV71 infection causes various types of programmed cell death. However, there are currently no clinically approved specific antiviral drugs for control of EV71 infection. Astragalus membranaceus (AM), a Traditional Chinese medicine, has been used in antiviral therapy in China. The aim of the present study was to determine whether total astragalosides (ASTs), bioactive components of AM, protect against EV. DAPI nuclear staining was used to observe morphological changes of the nucleus and the protective effect of ASTs, which revealed that the nucleus shrank following EV71 infection, while ASTs reversed it. Cell Counting Kit-8 assay found that human normal gastric epithelial cell (GES-1 cell) viability decreased following EV71 infection, while lactate dehydrogenase (LDH) assay showed that EV71 infection induced GES-1 cell damage. Western blotting was used to measure the expression levels of apoptosis and pyroptosis marker protein to determine whether EV71 infection induced apoptosis and pyroptosis in GES-1 cells. Reverse transcription-quantitative PCR was used to determine the anti-EV71 effect of ASTs. The results showed that ASTs protected GES-1 cells from EV71-induced cell apoptosis and pyroptosis. Furthermore, the present data demonstrated that the protective effect of ASTs was exerted by suppressing EV71 replication and release. These findings suggested that ASTs may represent a potential antiviral agent for the treatment of EV71 infection.

Highly Dispersed Mo2 C Nanodots in Carbon Nanocages Derived from Mo-Based Xerogel: Efficient Electrocatalysts for Hydrogen Evolution.

The production of hydrogen via electrochemical water splitting has the potential to enable the utilization of hydrogen-powered fuel cells on a large scale. However, to realize this technology, inexpensive, noble metal-free electrocatalysts possessing high performances for the hydrogen evolution reaction (HER) are needed. Mo2 C nanoparticles recently receive much attention as alternative noble metal-free electrocatalysts because their electronic structures are akin to that of Pt. However, the synthesis of Mo2 C at nanoscale with high catalytic activity for HER remains a great challenge. Moreover, although efforts have been made to prevent their aggregation, the particles coalesce during high temperature carbonization, which is typically used to produce such transition metal carbides. Here, the synthesis of Mo2 C nanodots that are well-dispersed within 3D cage-like carbon microparticles using rationally designed Mo-based xerogels, which are prepared via the sol-gel process as precursors, is reported. During their pyrolysis, the xerogels maintain their structures while the Mo species in them transform into well-dispersed Mo2 C nanodots in situ. The as-synthesized Mo2 C nanodots exhibit excellent electrocatalytic activity for HER, in both alkaline and acidic media, while remaining largely stable. The work also demonstrates a promising synthetic route and procedure to other well-dispersed yet stable nanocatalysts.

Effects of Age and Sex on Properties of Lumbar Erector Spinae in Healthy People: Preliminary Results From a Pilot Study.

Background: The influences of age and sex on properties of lumbar erector spinae have not been previously studied. Changes in the performance of lumbar erector spinae properties associated with age represent a valuable indicator of risk for lower-back-related disease. Objective: To investigate the lumbar erector spinae properties with regard to age and sex to provide a reference dataset. Methods: We measured muscle tone and stiffness of the lumbar erector spinae (at the L3-4 level) in healthy men and women (50 young people, aged 20-30 years; 50 middle-aged people, aged 40-50 years; and 50 elderly people, aged 65-75 years) using a MyotonPRO device. Results: In general, there are significant differences in muscle tone and stiffness among young, middle-aged, and elderly participants, and there were significant differences in muscle tone and stiffness between men and women, and there was no interaction between age and sex. The muscle tone and stiffness of the elderly participants were significantly higher than those of the middle-aged and young participants (P < 0.01), and the muscle tone and stiffness of the middle-aged participants were significantly higher than those of the young participants (P < 0.01). In addition, the muscle tone and stiffness of men participants were significantly higher than that of women participants (P < 0.01). Conclusion: Our results indicate that muscle tone and stiffness of the lumbar erector spinae increase with age. The muscle tone and stiffness of the lumbar erector spinae in men are significantly higher than in women. The present study highlights the importance of considering age and sex differences when assessing muscle characteristics of healthy people or patients.

Design and Synthesis Strategies: 2D Materials for Electromagnetic Shielding/Absorbing.

Two-dimensional (2D) materials possess special physical and chemical properties. They have been proved to have potential application advantage in the microwave absorption (MA) and electromagnetic interference (EMI) shielding. Particularly, they exhibit positive shielding and absorbing response to EMI. Here, the research progress of preparation, electromagnetic performance and microwave shielding/absorbing mechanisms of 2D composite materials are introduced. Effective preparation routes including introducing heteroatoms, constructing unique structures and 2D composite materials are described. Furthermore, the application prospects and challenges for the development of novel EMI materials are expatiated.

Synthesis of Ultrathin and Grid-Structural Carbon Nanosheets Coupled with Mo2 C for Electrocatalytic Hydrogen Production.

Molybdenum carbide possessing a Pt-like d-band electronic structure is considered as one of potential candidates of electrocatalysts and it shows intrinsic catalytic property. However, a high carbonizing temperature easily leads to the coalescence of nanoparticles (NPs). Here, we propose a simple sol-gel route to achieve high dispersity of carbide NPs by designing a Mo-involved xerogel. The results show that molybdenum carbide NPs are dispersed and anchored on the nitrogen-doped carbon nanosheets (Mo2 C@NC). Ultrathin carbon layers resemble graphene and the network structures act as a support of carbide NPs, which can hinder NPs' coalescence effectively. Nanpoparticles cross-coupled on network-structure nanosheets display the grid shapes. Electrochemical studies indicate that Mo2 C@NC material exhibits outstanding hydrogen evolution performance in alkaline electrolyte.

RIPK1 contributes to cisplatin-induced apoptosis of esophageal squamous cell carcinoma cells via activation of JNK pathway.

AIMS: Previous studies have uncovered the function of receptor-interacting protein kinase 1 (RIPK1) to mediate both cell survival and death. Moreover, RIPK1 modulates apoptosis and necroptosis depending on its activity, phosphorylation or ubiquitylation status. Many studies have explained the role or mechanism of RIPK1 in necroptosis. However, the role of RIPK1 has not been elucidated fully in human esophageal squamous cell carcinoma (ESCC) cells. MATERIALS AND METHODS: The protein and mRNA expression levels of RIPK1 in a panel of ESCC cell lines by Western blot and real-time quantitative reverse transcription PCR (qRT-PCR) were analyzed. MTS assay was used to examine cellular proliferation, flow cytometric analysis to detect apoptosis, mitochondrial membrane potential and reactive oxygen species production. ESCC cells with either inhibitor or overexpressed RIPK1were analyzed to determine cell proliferation, colony formation and apoptosis. Flow cytometry and western blotting assays were used to explore the underlying mechanism. KEY FINDINGS: In our study, RIPK1 expression was found to contribute significantly to cisplatin-induced apoptosis in the human ESCC cells. The reduced RIPK1 expression promoted cells proliferation and overexpressed RIPK1 facilitated cell apoptosis. Mechanistic investigations have revealed that the inhibition of proliferation for RIPK1 in ESCC cells was regulated via activation of c-Jun NH2-terminal kinase signaling. Additionally, damages were observed in the mitochondrial membrane, depletion of ATP and increased generation in reactive oxygen species. SIGNIFICANCE: Our findings verified the evidence that RIPK1 can promote cell death in ESCC cells, with potential implications for activating c-Jun NH2-terminal kinase pathway as a novel approach to the disease.

Effects of bushen huoxue method for knee osteoarthritis: A protocol for systematic review and meta-analysis.

BACKGROUND: Knee osteoarthritis (KOA) is a common progressive joint disorder in old people. Bushen huoxue (BSHX) is a classical method of TCM in treating KOA. However, there is no systematic review related to BSHX for KOA. The purpose of this study is to provide a comprehensive and reliable evaluation of the clinical evidence of BSHX in the treatment of KOA. METHODS: We searched relevant studies on BSHX for KOA from the databases of PubMed, Embase, MEDLINE, Cochrane Library Central Register of Controlled Trials, China national knowledge infrastructure database (CNKI), Wan fang database, Chongqing VIP information, and SinoMed from their inception to May 2020. Two researchers will select and evaluate qualified studies independently. The primary outcomes of this review will focus on pain intensity. The meta-analyses will be performed by using the RevMan 5.3. RESULTS: The study will provide a comprehensive evaluation of the efficacy and safety of the BSHX method for patients with KOA. CONCLUSION: The results of this systematic review will provide evidence to judge whether BSHX is an effective intervention for patients with KOA.

Effects of bushen qianggu method for primary osteoporosis: A protocol for systematic review and meta-analysis.

BACKGROUND: Primary osteoporosis (POP) is one of the most common orthopedic diseases with a high risk of fracture. Effective treatment of POP is of great significance to reduce the rate of disability and improve the quality of life. Bushen qianggu (BSQG) is a classical method of TCM in treating POP. However, there is no systematic review related to BSQG for POP. The purpose of this study is to provide a comprehensive and reliable evaluation of the clinical evidence of BSQG in the treatment of POP. METHODS AND ANALYSIS: Relevant randomized controlled trial literature evaluating the effect of BSQG on patients with POP will be obtained by searching the PubMed, Embase, MEDLINE, Cochrane Library Central Register of Controlled Trials, China national knowledge infrastructure database, Wan fang database, Chongqing VIP information, and SinoMed from their inception to May 2020. Two researchers will select and evaluate qualified studies independently. The bone mineral density value and the incidence of fractures will be accepted as the primary outcomes. The meta-analyses will be performed by using the RevMan 5.3. RESULTS: This study will provide a comprehensive evaluation of the efficacy and safety of BSQG method for patients with POP. CONCLUSION: The conclusion of our systematic review will provide evidence to judge whether BSQG is an effective intervention for patients with POP. TRIAL REGISTRATION NUMBER: 10.17605/OSF.IO/ZMX3W.

High Platelet Levels Attenuate the Efficacy of Platinum-Based Treatment in Non-Small Cell Lung Cancer.

BACKGROUND/AIMS: The correlation between platelet levels and clinical outcomes has received increasing attention, but it is not yet clear whether and how platelet levels affect the therapeutic response in non-small cell lung cancer (NSCLC). In the current study, we aimed to explore the role of platelet levels in responsive to platinum-based chemotherapy and investigated the underlying mechanism. METHODS: We evaluated the possibility of platelet level as a biomarker for response to platinum-based therapy in NSCLC by retrospective analysis of NSCLC patients. Cell proliferation was evaluated using cell counter and flow cytometry. Cell capillary-like structures of HPMEC were estimated with ECMatrix. The effect of platelets on A549, H1299, and HPMEC apoptosis was measured by flow cytometry. A A549-bearing NOD/ SCID mice model was employed to determine whether platelets could counteract cisplatin-induced apoptosis in vivo. In vivo cell proliferation and apoptosis were evaluated with Ki-67 antibody and TUNEL staining respectively. The angiogenesis of tumor was estimated by CD31 microvessel density. The protein levels of Akt, Bad and Bcl-2 were assessed by western blot. To further examine platelet-driven effects of the chemotherapeutic response, we used platelet depletion and platelet transfusion in A549-bearing NOD/SCID mice. RESULTS: Thrombocytosis at NSCLC diagnosis was associated with lower progression-free survival and median overall survival. Platelet levels before chemotherapy in the no response group were markedly higher than in the responsive group. Platelets rescued the inhibition of cell proliferation and angiogenesis and protected against cell apoptosis induced by cisplatin, platelets rescued cisplatin-induced apoptosis via the Akt/Bad/Bcl-2 signaling pathway under endoplasmic reticulum stress. Platelet transfusion decreased the therapeutic effect of cisplatin, while it was increased by platelet depletion. CONCLUSION: We confirmed an important anti-apoptosis mechanism mediated by platelets and found that platelets could counteract cisplatin-induced apoptosis. Reducing platelet levels or blocking platelet-based cytoprotection may represent new methods for improving the chemotherapeutic effect.

Direct Position Determination of Unknown Signals in the Presence of Multipath Propagation.

A novel geolocation architecture, termed "Multiple Transponders and Multiple Receivers for Multiple Emitters Positioning System (MTRE)" is proposed in this paper. Existing Direct Position Determination (DPD) methods take advantage of a rather simple channel assumption (line of sight channels with complex path attenuations) and a simplified MUltiple SIgnal Classification (MUSIC) algorithm cost function to avoid the high dimension searching. We point out that the simplified assumption and cost function reduce the positioning accuracy because of the singularity of the array manifold in a multi-path environment. We present a DPD model for unknown signals in the presence of Multi-path Propagation (MP-DPD) in this paper. MP-DPD adds non-negative real path attenuation constraints to avoid the mistake caused by the singularity of the array manifold. The Multi-path Propagation MUSIC (MP-MUSIC) method and the Active Set Algorithm (ASA) are designed to reduce the dimension of searching. A Multi-path Propagation Maximum Likelihood (MP-ML) method is proposed in addition to overcome the limitation of MP-MUSIC in the sense of a time-sensitive application. An iterative algorithm and an approach of initial value setting are given to make the MP-ML time consumption acceptable. Numerical results validate the performances improvement of MP-MUSIC and MP-ML. A closed form of the Cramér-Rao Lower Bound (CRLB) is derived as a benchmark to evaluate the performances of MP-MUSIC and MP-ML.

Efficient Catalysts for Cyclohexane Dehydrogenation Synthesized by Mo-Promoted Growth of 3D Block Carbon Coupled with Mo2C.

Cyclohexane can serve as a good dihydrogen (H2) carrier and a safer medium to store and transport H2, as it is liquid under ambient conditions and it has a relatively high hydrogen density per unit volume (0.056 g(H2)/cm3(Cy)liq.). However, cyclohexane can release H2 only with efficient cyclohexane dehydrogenation catalysts. Here, we report the synthesis of three-dimensional micron-sized block carbon-molybdenum carbide (BCMC) composite materials that can serve as noble-metal-free catalysts for cyclohexane dehydrogenation. The materials are synthesized by a facile hydrothermal synthetic route, and their structures and morphologies are characterized by various analytical techniques. The results show that the BCMCs, along with specific morphologies, form when a source of Mo is included in the precursor and that the sizes of the microparticles in them can be tailored by changing the relative amount of Mo used for their synthesis. The as-synthesized BCMC materials exhibit high catalytic activity for cyclohexane dehydrogenation while remaining stable and maintaining their catalytic activities during the reaction. The materials' catalytic activity increases as the amount of Mo used to make the materials is increased. This is further found to be because the BCMC materials containing higher amounts of ammonium molybdate or higher densities of Mo2C provide substantially lower activation energies for the reaction. These materials can be expected to find industrial applications for catalytic production of H2 from hydrocarbons.