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Polycarbonsilane (PCS) is an important precursor of silicon carbide (SiC) fibers and ceramics. The ceramic yield of PCS is relatively low, about 60 %, which may bring some deficiencies in its applications. In this work, a novel precursor cyano-polycarbosilane (PCSCN) is synthesized by hydrosilylation reaction between PCS and acrylonitrile using a rhodium-containing catalyst, although acrylonitrile is generally not easy for hydrosilylation. After introducing tiny amounts of cyano (-C≡N) groups into the PCS molecules, the ceramic yield of PCSCN can increase largely to over 80 %. The ceramization mechanism of PCSCN is investigated by FTIR, TG, XPS, ESR, NMR, Raman and XRD analyses. It is found that some crosslinking structures in PCSCN are formed between Si H bonds and C N groups from about 200 ℃, which can be responsible for the high ceramic yield. The existence of a little more N, O and free C elements in the pyrolysis products may inhibit the growth of crystalline β-SiC. Moreover, the PCSCN precursor can also be melt-spun into continuous fibers by tailoring its molecular weight and softening point. The oxidized PCSCN fiber with relatively low oxygen content can be pyrolyzed without melting, and the final SiC fiber with an oxygen content as low as 8.5 % is obtained.

Activated carbon particle electrodes modified by oxygen or nitrogen groups could be promising electrode candidates for capacitive deionization (CDI) processes. In this work, activated carbon particle electrodes were modified by phosphoric acid, nitric acid, urea, melamine, and zinc chloride to enhance desalination of an aqueous electrolytic solution. The modified activated carbon particles were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller measurements and electrochemical scanning. The electrodes with oxygen or nitrogen groups on the surface exhibited a much higher desalination capacity and charge efficiency than those without any surface modification. Particularly, the activated carbon particle electrode modified by phosphoric acid exhibited a desalination capacity of 15.52 mg/g at 1.4 V in 500 mg/L NaCl solution, which was approximately eight times that of the unmodified electrode (2.46 mg/g). The enhancement was attributed to a higher specific capacitance, a lower electrochemical impedance and an increase in oxygen or nitrogen-containing groups on the surface.

Objectives: To compare the efficacy and safety of anterior temporal lobotomy (ATLo) and anterior temporal lobectomy (ATLe) in drug-resistant temporal lobe epilepsy.Methods: Patients diagnosed with pharmacoresistant temporal lobe epilepsy who underwent anterior temporal lobotomy (ATLo) or anterior temporal lobectomy (ATLe) performed by a single surgeon were retrospectively included. Every patient was followed up annually after surgery. The postoperative seizure outcome evaluation was based on the Engel and ILAE classifications. We compared postoperative complications and 2-year follow-up seizure outcomes between the ATLo group and the ATL group.Results: A total of 42 individuals (21 ATLo and 20 ATLe) were included. At the two-year follow-up, more patients in the ATLo group than the ATLe group had reached Engel class I (20 versus 14) and ILAE I (19 versus 13). However, these differences were not significant. One patient in the ATLo group had intraparenchymal hematoma and fully recovered. The two groups had similar incidences of other short-term complications, and no patients died or had any permanent complications.Discussion: ATLo is not inferior to ATLe for patients with drug-resistant temporal epilepsy. There was no significant difference in seizure outcomes or the rate of postoperative complications between the two groups. A large sample randomized control study is needed.

The as-extruded Mg-xLi-3Al-1Zn (x = 1, 3, 5; wt%) sheets (LAZ131, LAZ331 and LAZ531 respectively) were performed with different reductions in multi-pass cold-rolling process. The changed mechanical behaviors of cold-rolled AZ31 alloys with Li additions were investigated via the electron-backscattered diffraction (EBSD) and texture. The results indicated that the main deformation modes of LAZ131 alloy were twinning and basal slip during cold rolling process. However, for the LAZ331 and LAZ531 alloy, the prismatic slip, { 11 2 2 } pyramidal slip, {10 1 2} extension twining, {10 1 1} contraction twinning sequentially dominated in the deformation with increased rolling reduction. Then, the theoretical critical shear strength ( τ max ) (reflecting the critical resolved shear stress, CRSS) of Mg and Mg-Li crystal was characterized by first-principles calculation. The direct consequences from calculations indicated that the value of τ max decreased from 1571 MPa to 1276 MPa in pyramidal slip systems, while that increased from 114 MPa to 177 MPa in basal slip, due to doping Li to Mg single crystal. The decrease in τ max ratio between non-basal and basal may promote an easy activation of non-basal slip and show different deformation modes of cold-rolled AZ31 alloys with different Li additions.

Introduction Chorea-acanthocytosis (ChAc) is an autosomal recessive hereditary disorder caused by the mutation of gene VPS13A. Deep brain stimulation of ChAc has made substantial progress in the recent decades. However, the reports were scattered across centers and performed by different neurosurgeons. Here, we report a case series consisting of six patients diagnosed with ChAc, receiving bilateral high-frequency stimulation of globus pallidus internus (GPi) in a single center. Methods We report six consecutive patients diagnosed with ChAc and present a review of the literature. All patients received neurological evaluations using the Unified Huntington's Disease Rating Scale (UHDRS) motor score before surgery and during clinical follow-ups. One patient was observed over six months, while five patients were seen over 12 months. Results All patients underwent high-frequency stimulation ranging from 130 Hz to 175 Hz. In the follow-up period, a general trend was found toward higher amplitude and broader pulse widths, with a mean current range of 2.08 mA to 3.06 mA and a mean pulse width range of 75 μsec to 98 μsec. On preoperative evaluation, the mean UHDRS motor score was 35.7 ± 16.3 and the chorea subscore was 11.3 ± 4.7. At the three-month postoperative follow-up, both UHDRS motor score (13.5 ± 5.8) and chorea subscore (3.0 ± 1.2) reached valley values. Thereafter, the UHDRS motor score and chorea subscore showed a gradual rise, reaching 19.2 ± 5.9 and 4.8 ± 1.7, respectively, at the 12-month follow-up. In addition, adverse events were also seen. Patient 1 developed dysarthria six months after surgery, whereas Patient 6 had a generalized tonic-clonic seizure attack one day after surgery CONCLUSION: High frequency stimulation of the GPi is an effective and safe modality for the treatment of ChAc, with both rapid symptomatic improvements and steady chronic outcomes.

The recently developed non-equiatomic high entropy alloy (HEA), Fe80-xMnxCo10Cr10, overcoming the strength-ductility trade-off. Phase stability in Fe80-xMnxCo10Cr10 is reduced via tailoring Mn content, resulting in a single phase or dual-phase microstructure (face-centered cubic (FCC) phase and hexagonal close packed (HCP) phase). In this work, the plastic deformation and annealing behaviors during processing in two as-cast non-equiatomic HEAs with coarse grains, i.e., Fe30Mn50Co10Cr10 with single-phase (FCC) and Fe60Mn20Co10Cr10 with dual-phase (FCC+HCP), are investigated by a combination of electron back-scattered diffraction and transmission electron microscope. Plastic strain of Fe30Mn50Co10Cr10 is mediated by dislocation slip via forming interacting planar arrays of dislocations, { 111 } deformation twins and micro-shear bands. In Fe60Mn20Co10Cr10, it is revealed a synergy of multiple deformation mechanisms, involved dislocation slip and transformation induced plasticity (TRIP, FCC→HCP). More interestingly, it is revealed { 10 1 ¯ 2 } deformation twins and e martensite plates with the special misorientation ( 70.5 ° / 11 2 ¯ 0 > ) in the HCP phase. This work further confirms Mn content can act as a switch for TRIP effect in Fe80-xMnxCo10Cr10 HEA. Upon annealing treatments, profuse annealing twinning boundaries in Fe30Mn50Co10Cr10 and dense boundaries with 70.5 ° / 11 2 ¯ 0 > in Fe60Mn20Co10Cr10 are formed, paving the way for the development of HEA with the superb mechanical performance.

Feasibility of dechlorination using ultra-high lime with aluminum process (UHLA) has been demonstrated by previous studies. However, the negative influences of UHLA on water qualities (pH, conductivity, and residual calcium concentration) after dechlorination and the products generated in dechlorination process have not been thoroughly analyzed. In this study, changes of water qualities at various dechlorination conditions were investigated, and favorable conditions for Friedel’s salt formation were explored by X-ray diffraction analysis. The pH and conductivity after dechlorination increased with the improvement of chloride removal effect. The calcium ion concentration in effluent also fluctuated with different dosages of CaO. At the maximum chloride removal efficiency of 71.4%, the pH, conductivity, and calcium ion concentration in effluent were 12.8, 10.9 ms/cm, and 22.7 mg/L, respectively. X-ray diffraction analysis for precipitants indicated that Friedel’s salt with the highest purity was also generated at the optimal dechlorination efficiency. The high dechlorination efficiency of 80.5% was achieved with the development of a stepwise addition strategy. Chemical costs for treating one ton of wastewater containing 500 mg/L chloride were $3.96.

To reduce the risk of roof falling and rib spalling during equipment retracement in thin coal seam faces with soft roofs, the 25070 working face of Xuehu Coal Mine was taken as the research object, and theoretical analysis, numerical simulation, and field practice methods were used. Under different space relationships between retracement channels and main roof fracture, the load of hydraulic supports was quantitatively analyzed. The relationship between the working resistance of the hydraulic support and the sinking rotation angle of the immediate roof was analyzed, and a reasonable time for the arrangement of the retracement channel was determined. The sublevel excavation technology and the combined support technology of roof anchor cables and coal rib anchors were proposed. The field application shows that the falling height and rate of movable prop of the hydraulic supports, working resistance of the hydraulic supports, and the roof subsidence all meet the requirements of safety production during the terminal mining period, and the surrounding rock control effect of retracement channel was determined to be good. The safe and efficient mining of the coal mine is ensured, and the research results can provide guidance for similar working faces.

Objectives: To detect and compare the features of interictal perfusion and volume asymmetry between temporal lobe epilepsy (TLE) patients with and without hippocampal sclerosis (HS).Methods: Sixty-one TLE patients (mean age 28.4 ± 9.3 years; 28 female/33 male) with unilateral signs of HS (TLE-HS+) and 25 TLE patients (mean age 29.8 ± 8.0 years; 17 female/8 male) without HS (TLE-HS-) were included. Thirty healthy volunteers served as controls (mean age 26.0 ± 8.7 years; 22 female/8 male). Brain segmentation and volume calculation were performed. Quantitative cerebral blood flow (CBF) values were measured based on arterial spin labeling (ASL). The asymmetry indices (AIs) of volume and perfusion were calculated.Results: TLE-HS+ (adjusted P = 0.001) and TLE-HS- patients (adjusted P = 0.006) had significantly higher hippocampal perfusion AIs than controls. TLE-HS+ and TLE-HS- had similar hippocampal perfusion AIs (adjusted P = 1.00). TLE-HS+ had higher hippocampal volume AIs than TLE-HS- and controls (adjusted P < 0.001). TLE-HS- and controls had similar hippocampal volume AIs (adjusted P = 1.00). All (100%) TLE-HS+ patients had positive hippocampal perfusion or volume AIs. No significant correlation between the AIs of hippocampal perfusion and volume was found in both TLE-HS+(P = 0.894) and TLE-HS- (P = 0.106) patients. TLE-HS+ patients demonstrated more extensive whole-brain asymmetry of both perfusion and volume than TLE-HS- patients.Conclusion: TLE-HS+ and TLE-HS- patients have different patterns of whole-brain perfusion and volume asymmetry. Hippocampal perfusion asymmetry was revealed in both TLE-HS+ and TLE-HS- patients.

Ultra-strong medium entropy alloy (VCoNi) is designed via severe lattice distortion. Simulation calculation suggests the stacking fault energy of VCoNi can be reduced as increasing Ta contents, but keep the deformation twinnability almost unchanged. The experiment result suggests Ta addition can’t remarkably increase the deformation twinning propensity due to the chemical short-range order in VCoNi.