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We report the design, synthesis, structure, and properties of two complex layered phosphide nitrides, $Ak$Th$_2$Mn$_4$P$_4$N$_2$ ($Ak$ = Rb, Cs), which contain anti-fluorite-type [Mn$_2$P$_2$] bilayers separated by fluorite-type [Th2N2] layers as a result of the intergrowth between AkMn$_2$P$_2$ and ThMnPN. The new compounds are featured with an intrinsic hole doping associated with the interlayer charge transfer and a built-in chemical pressure from the [Th$_2$N$_2$] layers, both of which are reflected by the changes in the lattice and the atomic position of phosphorus. The measurements of magnetic susceptibility, electrical resistivity, and specific heat indicate existence of local moments as well as itinerant electrons in relation with d-p hybridizations. The expected dominant antiferromagnetic interactions with enhanced d-p hybridizations were demonstrated by the first-principles calculations only when additional Coulomb repulsions are included. The density of states at the Fermi level derived from the specific-heat analysis are 3.5 and 7.5 times of the calculated ones for Ak = Rb and Cs, respectively, suggesting strong electron correlations in the title compounds.

The incidence of atherosclerosis (AS), a major contributor to cardiovascular disease, is steadily rising along with an increasingly older population worldwide. Pyroptosis, a form of inflammatory programmed cell death, determines the release of pro-inflammatory mediators by endothelial cells, smooth muscle cells, and atheroma-associated macrophages and foam cells, thereby playing a critical role in AS progression. Canonical pyroptosis is mediated by inflammasome formation, activation of caspase-1, and maturation and release of proinflammatory cytokines. Electrical stimulation (ES) is a noninvasive, safe therapy that has been shown to alleviate symptoms in several health conditions. Here, we investigated the anti-inflammatory and anti-pyroptotic effects of ES in human THP-1 macrophages treated with the dipeptidyl peptidase inhibitor Val-boroPro (VbP). We found that ES downregulated NOD-like receptor family protein 3 (NLRP3) inflammasome, ASC, and caspase-1 expression and abrogated the release of Interleukin-1β (IL-1β) and Interleukin-18 (IL-18), indicating effective pyroptosis inhibition. These changes were paralleled by a reduction in reactive oxygen species (ROS) production, reversal of VbP-induced sirtuin3 (Sirt3) downregulation, deacetylation of ATG5, and induction of autophagy. These findings suggest that ES may be a viable strategy to counteract pyroptosis-mediated inflammation in AS by raising Sirt3 to promote autophagy and inhibit ROS generation.

Mn-based ZrCuSiAs-type pnictides ThMnPnN (Pn = P, As) containing PbO-type Th2N2 layers were synthesized. The crystal and magnetic structures are determined using X-ray and neutron powder diffraction. While neutron diffraction indicates a C-type antiferromagnetic state at 300 K, the temperature dependence of the magnetic susceptibility shows cusps at 36 and 52 K respectively for ThMnPN and ThMnAsN. The susceptibility cusps are ascribed to a spontaneous antiferromagnetic-to-antiferromagnetic transition for Mn2+ moments, which is observed for the first time in Mn-based ZrCuSiAs-type compounds. In addition, measurements of the resistivity and specific heat suggest an abnormal increase in the density of states at the Fermi energy. The result is discussed in terms of the internal chemical pressure effect.

We collected in situ high-temperature powder X-ray diffraction (XRD) patterns, as well as Raman and Fourier transform infrared (FTIR) spectra on a natural serandite sample. The volumetric thermal expansion coefficient αV (K−1) is determined as a linear function of T (K): 37.6(5) × 10−9 × T + 11.1(3) × 10−6, with an averaged value of 31.7(10) × 10−6 K−1, while the anisotropy of axial thermal expansivities shows the order of αa > αb > αc. The isobaric Gruneisen parameters γiP are constrained as: 0.2–1.6 for most of the lattice vibrations below 500 cm−1; while 0–0.6 for the O–Si–O bending and Si–O stretching modes inside the Si3O9 chains above 500 cm−1. As compared with common silicate phases in the upper mantle and the transition zone, the γiP parameters for the internal vibrations are significantly smaller in silicate chains (serandite, enstatite) than those in Si2O7 groups (wadsleyite) and isolated SiO4 units (forsterite, pyrope), since the rotation of the bridging O atoms (in the direction perpendicular to Si–O–Si) could relax the SiO4 tetrahedra at elevated temperature. The OH-bending vibration of serandite is observed in both Raman-active (1378 cm−1) and IR-active (1389 cm−1) modes, with a temperature-dependence of − 0.07 and − 0.09 cm−1/K, respectively. The red-shift of these OH-bending modes with increasing temperature indicates that the hydrogen bond gets weaker as the O3…O4 distance becomes larger during thermal expansion. Additionally, our polarized FTIR spectra confirm that the stretching mode of the very strong hydrogen bond, a broad absorption region (1400–3300 cm−1), is polarized in the direction of E//b, as reported by Hammer et al. (Am Mineral 83:569–576, 1998).

The effect of powder characteristics on the thermal conductivity and mechanical properties of silicon nitride (Si 3 N 4 ) ceramics were investigated systematically by using two α-Si 3 N 4 powders a ...

We have synthesized a new series of layered oxyselenides Bi 2 LnO 4 Cu 2 Se 2 (Ln=Nd, Sm, Eu, Dy, Er, Yb). Their crystal structures and physical properties were studied through X-ray diffraction, electric transport measurements, bulk magnetization and first-principle calculation. All these compounds have a tetragonal structure with space group I4/mmm. They exhibit hole-type metallic behaviours which is also verified by the DFT calculation. The new Bi 2 LnO 4 -type block in these compounds may give people some enlightenment in synthesizing new iron-based superconductors or other layered compounds.

Neuroinflammation is one of the major processes that trigger neuropathological amyloid-β (Aβ) deposition and contribute to Alzheimer’s disease (AD) progression. Naked mole rats, which are the longest living rodents and exhibit negligible senescence, have a special brain microenvironment characterized by high-molecular-mass hyaluronan (HMM-HA) and high levels of neuregulin 1 (NRG1), which are related to resistance to neuroinflammation and Aβ deposition, leading to protection from AD. Thus, mimicking the unique brain microenvironment of the naked mole rat as a strategy for AD treatment is of critical interest. Here, naked mole rat HMM-HA and NRG1 were used to establish an injectable neuroinflammation-responsive triglycerol monostearate (TM)-HA-NRG1 hydrogel to alter the brain microenvironment in the early to late stages of AD. Intracerebroventricular (ICV) delivery of the hydrogel resulted in significant mitigation of Aβ plaque formation and complement C1q deposition in the hippocampus. Interestingly, we found that C1q deposition on pericytes was probably associated with capillary dysfunction. Furthermore, continuous intervention obviously reduced C1q deposition on pericytes and improved the oxygen supply to the brain. Importantly, in 16-month-old AD mice, cognitive decline was significantly ameliorated after TM-HA-NRG1 hydrogel treatment. Thus, the work reported here provides a potential early intervention strategy for retarding later AD progression.

A member of antiperovskite manganese compound Mn3PdN was successfully synthesized. The structural, magnetic, electrical, and thermal transport properties were investigated systematically. The results indicated that Mn3PdN is a weak correlated system. A first-order paramagnetic (PM) to antiferromagnetic (AFM) transition occurred at 285 ​K (TN) combining with an abrupt change in structure. Mn3PdN exhibits multifunctional properties such as near-zero temperature coefficient of resistivity (TCR) and negative thermal expansion (NTE).

Herein, Dy3+ doped indium nitride nanosheets with ferromagnetism at room-temperature were synthesized via a vapor - solid phase nitriding reaction. The as-synthesized samples exhibit clear ferromagnetism at room-temperature. The ferromagnetic properties of the samples could be changed by doped Dy3+. The saturation magnetization value of various Dy3+ doped indium nitride nanosheet samples display a parabolic-like change with the Dy3+ doped content increase and reaches the top value of 0.1455 emu g−1 corresponding to the Dy3+ doped content of 1.06 at. % at room temperature. The magnetic properties were originated from the d-f interaction between localized carriers and adjacent rare earth Dy3+ ions in the carrier orbits based on the first-principles calculation. The as-synthesized Dy doped indium nitride nanosheets can be widely used in spintronic devices due to the room temperature ferromagnetism.

We report the results of X-ray diffraction and 57Fe Mossbauer spectroscopy study, complemented by ab-initio calculations of the electronic structure, hyperfine-interaction parameters, and elastic properties of the new 30 K superconductor ThFeAsN. The superconductor crystallizes in the tetragonal space group P4/nmm with the lattice parameters a = 4.0356(1) A and c = 8.5286(1) A. Contrary to the claims in the literature, we demonstrate unequivocally that there is no magnetic order of the Fe magnetic moments down to 2.0 K. It is suggested that the absence of Fe magnetism may be due to an internal uniaxial chemical pressure whose presence is manifested by the unusually small c/a ratio. Evidence is provided for the presence of a mixture of ionic and covalent chemical bonding and of metallic characteristics. A detailed analysis of the energy band structure of ThFeAsN is presented. The shape of the Mossbauer spectra is accounted for by a quadrupole doublet with a small quadrupole splitting that increases with decreasing temperature. Excellent agreement between the calculated and measured 0 K quadrupole splittings is observed. Fair agreement between the experimental Debye temperature of 332(2) K and the calculated one of 370 K is observed.

Tumor-targeted drug delivery systems with stimuli-response drug release have been increasingly used to improve the therapeutic efficacy of antitumor drugs. Here, we report a specific molecular recognition activation drug nanoplatform based on specially designed DNA sensor-capped doxorubicin (DOX)-loaded mesoporous silica nanoparticles (MSNs), designated as specific molecular recognition-activated nanoparticle (SMRAN). DNA sensors on the targeted nanoparticles can trigger DOX release through a conformational switch induced by MUC-1. This causes a significant difference in cell viability between breast cancer MCF-7 and normal breast Hs578bst cells (24.8% and 86.0%). In vivo experiments showed that the tumor volume was reduced 1.5-times in the SMRAN treatment group. Compared with that in the DOX group, due to significantly improved tumor accumulation and retention of DOX. The strategy of the MUC-1 activated drug delivery system is expected to provide a new perspective for clinical application.

We investigated the physical properties of the cobalt doped layered oxyselenides BiCu1-xCoxSeO. 5% Co doping led to a large increase in the Seebeck coefficient which should be attributed to the magnetic interactions with the magnetic moment carried by Co atoms. The carrier-type of the material is changed from p-type to n-type with 20% Co doping. We studied the thermoelectric property of Bi0.95Ca0.05Cu0.95Co0.05SeO. The dual-doping sample exhibits higher Seebeck coefficient than Ca single doped sample and the ZT was enhanced remarkably. A maximum ZT value of 0.11 was achieved for Bi0.95Ca0.05Cu0.95Co0.05SeO at 300 K.

Silicon nitride (Si3N4) ceramics are widely used in mechanical and thermal management applications due to their excellent properties. To overcome the difficulties in traditional Si3N4 ceramic forming techniques, it is interesting to see the possibility of making complex-shaped silicon nitride ceramic component with novel 3D printing methods. In this study, we aim to study the effect of photo-initiators on the curing behavior of pre-formulated Si3N4 ceramic UV resin suspension. To elucidate the potential multi-factor interactions, a statistic experiment design was implemented in a sequence of screening and optimization by using Modde software. It was found that the kinds of photo-initiators, total amount of initiators and the mixture ratio between initiators have a great influence on the curing properties of silicon nitride UV ceramic resin. Based on these results, a formula was selected based on the criterion of using least amount photo-initiator while reaching the highest curing thickness.

We use neutron powder diffraction to study on the non-superconducting phases of ThFeAsN$_{1-x}$O$_x$ with $x=0.15, 0.6$. In our previous results on the superconducting phase ThFeAsN with $T_c=$ 30 K, no magnetic transition is observed by cooling down to 6 K, and possible oxygen occupancy at the nitrogen site is shown in the refinement(H. C. Mao \emph{et al.}, EPL, 117, 57005 (2017)). Here, in the oxygen doped system ThFeAsN$_{1-x}$O$_x$, two superconducting region ($0\leqslant x \leqslant 0.1$ and $0.25\leqslant x \leqslant 0.55$) have been identified by transport experiments (B. Z. Li \emph{et al.}, J. Phys.: Condens. Matter 30, 255602 (2018)). However, within the resolution of our neutron powder diffraction experiment, neither the intermediate doping $x=0.15$ nor the heavily overdoped compound $x= 0.6$ shows any magnetic order from 300 K to 4 K. Therefore, while it shares the common phenomenon of two superconducting domes as most of 1111-type iron-based superconductors, the magnetically ordered parent compound may not exist in this nitride family., Comment: 4 pages, 4 figures

In this work, the TiO 2 -SrTiO 3 hybrids were synthesized by a facile hydrothermal reaction using TiO 2 as the titanium precursor under basic condition. By using the synthesized TiO 2 -SrTiO 3 hybrids as fillers, the films of the TiO 2 -SrTiO 3 /PVDF composites were prepared. The dielectric property and insulation behavior of the films were investigated. High permittivity and improved breakdown strength of the composites were achieved. The breakdown strength of the composites filled with 1 wt% hybrids exhibited an improvement about 80% compared with the unfilled PVDF matrix.

The adsorption isotherms and structural evolution of alkyl quaternary ammonium bromide (C n TAB) on graphite oxide (GO) were measured by means of an elemental analyzer, X-ray diffraction and Fourier transform infrared spectroscopy. In order to interpret the adsorption mechanism of surfactants onto GO, the adsorption kinetics and thermodynamics were further investigated. It was found that GO is a relatively efficient adsorbent within a wide range of temperatures (297–353 K), and the C n TAB was intercalated and then agglomerated into the interlayer spacing of GO via ionic bonding and hydrophobic bonding. The saturation amount of alkyl ammonium adsorbed on GO was decreased with the rise in temperature, and the experimental data fitted well into the modified Langmuir (Langmuir-Freundlich) equation. In addition, the negative values of ΔG and ΔH showed that the adsorption process of C n TAB onto the GO was spontaneous and exothermic.

Nosiheptide is one of the EU-approved sulfur-containing peptides in feed industry to inhibit the growth of the majority of Gram-positive bacteria. The main purpose of this study is directed to breed the high nosiheptide-producers by genome shuffling and ribosome engineering in Streptomyces actuosus AW7. The starting population for shuffling was generated by combining (60)Coγ-irradiation with LiCl mutagenesis treatments on the spores. After four rounds of protoplast fusion exposed to streptomycin as adaptive pressure, a high-yield recombinant strain D92 was obtained. In a 10-L fermenter, nosiheptide production reached 1.54 g/L which was 9.20-fold compared to that of the parental strain. Hyphae development, metabolic process, and ribosomal protein S12 sequence were investigated to characterize the differentiation among the recombinants. Several mutations in S12 were believed to be responsible to streptomycin resistance in the tested strain. The results demonstrated that the combination of genome shuffling and ribosome engineering is an efficient approach to breed high-yield industrial strains.

The zirconia-toughened-alumina (ZTA) composite powder was exposed to a prior ball milling treatment with a small amount of stearic acid (SA) before the traditional blending process. The effect of different amounts of stearic acid on surface properties of the powder, the particle size distribution of the powder, and the rheological properties of the suspension were systematically studied within the design of experiments. Fourier transformation infrared spectroscopy (FTIR) analysis was used to prove the chemical interaction between the stearic acid and the ZTA powder. The effects of SA content on the particle sizes and their distribution were carefully examined. Rheological properties such as viscosity, yield stress, and power law exponent of the suspensions were determined within a temperature range of 140–170 °C. The optimal content of SA to improve the properties of the suspensions was found to be 3 wt.%.

This paper introduces the studies of self-heat conserving facade panel with abandoned polypropylene fiber. The optimum process conditions were studied. The tensile properties, bending and impact properties of external insulation panel were tested. The results show that when the hot-pressing temperature is 180°C , the tensile, bending and impact of external insulation panel are best. The optimum process is hot-pressing temperature of 180 °C, hot pressure of 10MPa, hot-pressing time 12 Min. The physico-chemical properties were tested. The results show that the data of each test is up to the china national standard .The heat insulation property was tested, the results show that the panels have good insulation performance. The wallboard is light and easy to transport. Because the raw material adopts recycled polypropylene fibers, the price is low and the insulation is good. Recycled fiber-plastic composite is filled with bright future prospects.

We report the antimony (Sb) doping effect in a prototype system of iron-based supercon-ductors LaFeAsO1-yFy (y=0, 0.1, 0.15). X-ray powder diffraction indicates that the lattice pa-rameters increase with Sb content within the doping limit. Rietveld structural refinements show that, with the partial substitution of Sb for As, while the thickness of the Fe2As2 layers increases significantly, that of the La2O2 layers shrinks simultaneously. So a negative chemical pressure is indeed "applied" to the superconducting-active Fe2As2 layers, in con-trast to the effect of positive chemical pressure by the phosphorus doping. Electrical resis-tance and magnetic susceptibility measurements indicate that, while the Sb doping hardly influences the SDW anomaly in LaFeAsO, it recovers SDW order for the optimally-doped sample of y=0.1. In the meantime, the superconducting transition temperature can be raised up to 30 K in LaFeAs1-xSbxO1-yFy with x=0.1 and y=0.15. The Sb doping effects are discussed in term of both J1-J2 model and Fermi Surface (FS) nesting scenario., Comment: 7 pages, 4 figures, 1 table. to be published in Science in China Series G

A two-step pressure profile was used to prepare transparent MgAl2O4 ceramic without sintering aids by spark plasma sintering (SPS) at 1300 degrees C for 3 min. The influence of the pressure profile was investigated systematically and the discoloration in the present study was attributed to the dislocation formed during he fast densification in SPS. At low pre-load pressure, 5 MPa, with the normal characteristic fast heating rate (100 degrees C min(-1)), high inline transmittance of 51% at 550 nm and 85% at 2000 nm can be achieved. Keywords: Sintering; Oxide; Optical transmission; Dislocation; Ultrafine-grained microstructure

We report the synthesis and physical properties of a nickel-based arsenide ThNiAsN. The new compound crystallizes in a ZrCuSiAs-type structure (space group ) with lattice parameters and . Bulk superconductivity at is demonstrated by the measurements of electrical resistivity, dc magnetic susceptibility, and heat capacity. The upper critical field at zero temperature, , and the specific-heat jump at T c are 6.1 T and , respectively. These two physical quantities, together with the T c value, are the highest among the Ni-based ZrCuSiAs-type materials. We discuss this enhanced superconductivity in terms of the internal chemical pressure in ThNiAsN.

The new oxyselenide La(2)Co(2)Se(2)O(3), containing Co(2)O square-planar layers, has been successfully synthesized using solid-state reactions under vacuum. The compound crystallizes in space group I4/mmm with lattice parameters a = 4.0697(8) A and c = 18.419(4) A. Magnetic susceptibility measurements indicate an antiferromagnetic transition at approximately 220 K. The magnetic entropy associated with the transition is close to R ln 2, suggesting an unusual low-spin state for the Co(2+) ions. The as-prepared sample shows insulating behavior with room-temperature resistivity of approximately 10(7) ohms cm, which decreases by 4 orders of magnitude under a pressure of 7 GPa. Band structure calculations using the LSDA+U approach reproduce the insulating ground state with low spin for Co and suggest strong orbital polarization for the valence electrons near the Fermi level. It is also revealed that the spin and orbital degrees of freedom in the antiferromagnetic checkerboard spin-lattice are mutually coupled.

We have studied Ni-substitution effect in ${\text{LaFe}}_{1\ensuremath{-}x}{\text{Ni}}_{x}\text{AsO}$ $(0\ensuremath{\le}x\ensuremath{\le}0.1)$ by the measurements of x-ray diffraction, electrical resistivity, magnetic susceptibility, and heat capacity. The nickel doping drastically suppresses the resistivity anomaly associated with spin-density-wave ordering in the parent compound. Superconductivity emerges in a narrow region of $0.03\ensuremath{\le}x\ensuremath{\le}0.06$ with the maximum ${T}_{c}$ of 6.5 K at $x=0.04$, where enhanced magnetic susceptibility shows up. The upper critical field at zero temperature is estimated to exceed the Pauli paramagnetic limit. The much lowered ${T}_{c}$ in comparison with ${\text{LaFeAsO}}_{1\ensuremath{-}x}{\text{F}}_{x}$ system is discussed.

Stabilization of cobalt oxyhydrate superconductor was realized by post-treatment of the as-prepared superconductor in concentrated NaOH solution; this finding is expected to promote future experimental research on the intriguing material.

Stabilization of cobalt oxyhydrate superconductor was realized by post-treatment of the as-prepared superconductor in concentrated NaOH solution; this finding is expected to promote future experimental research on the intriguing material.

The graphite oxidation samples with different degrees of oxidation were prepared from natural flake graphite via a modified Hummers method with controlled addition of KMnO 4. The evolution of oxygen-containing functional groups was analyzed by Fourier transform infrared spectrometry (FT-IR) and X-ray photoelectron spectroscopy (XPS). The evolution rule of three-dimensional (3D) graphite structures during oxidation has been verified via X-ray diffraction (XRD). Experimental results show that the evolution of the interplanar spacing of samples during oxidation can be approximately divided into four stages. When the dosage of KMnO 4 is 0.5 g per 1 g of graphite (g/g), a graphite intercalation compound (GIC) is formed through intercalating reactions, and a slight increase is observed in the values of d100 and d110, suggesting that the π–π interactions which decrease the length of carbon–carbon bonds were partially disrupted. Adding additional KMnO 4 initiates the second stage, in which GIC begins to oxidize. The insertion of oxygen-containing functional groups in the graphene basal plane leads to dramatic changes in the values of d100 and d110. The d100 is greatly reduced while d110 increases slightly. These trends are attributed to the fact that the basal plane is stretched during the oxidation process. Further addition of KMnO 4 in the third stage leads to relatively small increases in the values of d100 and d110. This result is consistent with the evolution rule of hydroxyl groups. In this research, the evolution rule of the value of d001 is also clearly demonstrated. When the concentration of KMnO 4 is not more than 3.0 g/g, the value of products d001 keeps gradually increasing, indicating that oxygen-containing groups continue to form bonds with carbons in the basal plane, and that additional water molecules are adsorbed between the layers of the samples. All the interplanar spacing values (d001, d100 and d110) are reduced significantly in the fourth stage, when the amount of KMnO 4 added up to 4.0 g/g. FT-IR and XPS analyses demonstrate that the decrease in the values of d100 and d110 is due to a reduction in the content of external hydroxyl groups. The change in d001 is attributed to the partial release of water molecules confined in the interlayer spaces between adjacent sheets are partly released.

The results of x-ray diffraction, electrical resistivity, magnetic susceptibility, and (57)Fe and (155)Gd Mössbauer spectroscopy studies of polycrystalline samples of nonsuperconducting GdFeAsO and superconducting Gd(0.84)Th(0.16)FeAsO are reported. The superconductor Gd(0.84)Th(0.16)FeAsO has the onset transition temperature of 54.4(1) K. We find that Fe and Gd magnetic moments in GdFeAsO order antiferromagnetically at 132.7(1) K and 4.1(1) K, respectively. In Gd(0.84)Th(0.16)FeAsO, Fe atoms carry no magnetic moment down to 1.9 K whereas Gd magnetic moments order below 2.9(1) K. This is taken as evidence for the coexistence of Gd magnetic order and superconductivity. The Debye temperatures of GdFeAsO and Gd(0.84)Th(0.16)FeAsO are, respectively, 409(4) and 389(3) K.

Following the discovery of superconductivity in an iron-based arsenide LaO1-xFxFeAs with a superconducting transition temperature (Tc) of 26 K[1], Tc was pushed up surprisingly to above 40 K by either applying pressure[2] or replacing La with Sm[3], Ce[4], Nd[5] and Pr[6]. The maximum Tc has climbed to 55 K, observed in SmO1-xFxFeAs[7, 8] and SmFeAsO1-x[9]. The value of Tc was found to increase with decreasing lattice parameters in LnFeAsO1-xFx (Ln stands for the lanthanide elements) at an apparently optimal doping level. However, the F- doping in GdFeAsO is particularly difficult[10,11] due to the lattice mismatch between the Gd2O2 layers and Fe2As2 layers. Here we report observation of superconductivity with Tc as high as 56 K by the Th4+ substitution for Gd3+ in GdFeAsO. The incorporation of relatively large Th4+ ions relaxes the lattice mismatch, hence induces the high temperature superconductivity., 4 pages, 3 figures

Methanol was irradiated by 80 fs laser pulse, intensity range of 1013–1014 W/cm2. A TOF-mass spectrometer was coupled to the laser system and used to detect the ions produced. The parent ions CH3OH+ appeared firstly at the laser intensity of 1.4×1013 W/cm2. While the laser intensity was gradually increased, the parent ions were dissociated and the primary ions CH2OH+ were given as verified from the irradiation of deuterated methanol (CH3OD) showing the C—H bond cracking firstly. While the laser intensity was further increased to 2.0 × 1013 W/cm2, the C—O bonds of the parent ions also broke to give CH3+. When the laser intensity was higher, smaller fragment ions like CH+, C+, OH+ and O+ also appeared. Among the fragment ions, only H+ ion yield had anisotropic angular distribution dependence on the laser polarization vector in the dissociation of methanol. All the experimental observations show that the dissociation of methanol proceeds through stepwise mechanism but not Coulomb explosion.