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Keyhole is a defect which seriously restrains the industrial application of friction stir welding (FSW) technique. In this study, a new technique of non-keyhole friction stir welding (N-KFSW) was proposed, which could eliminate the keyhole during the in-situ welding process. Experiments were performed using a 6 mm thick 6061-T6 aluminum alloy plate under different rotating velocities. Due to the unexpected consumption of rotating sleeve during N-KFSW, the N-KFSW tool was simplified to a system consisting of a hollow sleeve and a clamping ring based on the working principle of N-KFSW. Compared with the solid sleeve, this hollow sleeve promoted the material flow below the sleeve. Therefore, the depth of the sleeve-stirring zone (SSZ) was equal to the thickness of the plate when the plunging depth was only 4.2 mm. The SSZ was divided into the sleeve directly affected zone (SDAZ) and the sleeve indirectly affected zone (SIAZ). The material in the SIAZ was transferred by the indirectly stirring effect of hollow sleeve, so the butt interface in the SIAZ was distributed as the S-shape line at the bottom of the SIAZ. The maximum tensile strength of 217.3 MPa was obtained at 1200 rpm, which was 71.5% of that of the base material. The height of the S-shape line shrunk with the rotating velocity increasing, and then governed that the fracture position of the joint transferred to the HAZ from the SSZ. The fracture surface morphology exhibited typical ductile fracture.

Three-dimensional (3D) heteroatom-doped nanostructured carbon materials have gained extensive attention because of their tremendous potential for enhancing supercapacitor performance. Herein, based on a mild carbonization/activation process we successfully developed green/sustainable 3D hierarchically porous nitrogen-doped nanostructure carbon (N–HNC) materials from houttuynia biomass, showing high specific capacitance and high cyclic stability. The as-prepared houttuynia-derived porous carbon material shows a unique flower-like architecture with well-distributed micro/meso pores and a high specific surface area of 2090 m2/g. The assembled supercapacitor based on N–HNC sample shows superior specific capacitance (473.5 F/g at 1 A/g) and remains over 50% of specific capacitance at 20 A/g. The N–HNC based symmetric supercapacitor, constructed with a two-electrode configuration, shows an energy density of 15.99 Wh/kg at 500 W/kg and outstanding capacitance retention of 95.74% even after 10,000 charge-discharge cycles at 10 A/g in an aqueous 6 M KOH electrolyte system. The results highlight the potential of the 3D porous N-doped hierarchical nano-structural carbon materials from houttuynia biomass as candidate electrodes for supercapacitor applications. This study provides an example of using the inherent framework structure of biomass as a precursor to synthesize hierarchically porous nitrogen-doped nanostructure for high-performance supercapacitor applications.

A numerical study on effects of hydrogen direct injection on hydrogen mixture distribution, combustion and emissions was presented for a gasoline/hydrogen SI engine. Under lean burn conditions, five different direct hydrogen injection timings were applied at low speeds and low loads on SI engines with direct hydrogen injection (HDI) and gasoline port injection. The results were showed as following: firstly, with the increase of hydrogen direct injection timing, the hydrogen concentration near the sparking plug first increases and then decreases, reaching the highest when hydrogen direct injection timing is 120°CA BTDC: Secondly, hydrogen can speed up the combustion rate. The main factor affecting the combustion rate and efficiency is the hydrogen concentration near the sparking plug: Thirdly, in comparing with gasoline, the NOX emissions with hydrogen addition increase by an average of 115%. For different hydrogen direct injection timings, the NOX emissions of 120°CA BTDC is the highest, which is 29.9% higher than the 75°CA BTDC. The hydrogen addition make the NOX emissions increase in two ways. On the one hand, the average temperature with hydrogen addition is higher. On the other hand, the temperature with hydrogen addition is not homogeneous, which makes the peak of temperature much higher. In a word, the main factor of NOX emissions is the size of high temperature zone in the cylinder: Finally, because the combustion is more complete, in comparing with gasoline, hydrogen addition can reduce the CO and HC emissions by 32.2% and 80.4% respectively. Since a more homogeneous hydrogen mixture distribution can influence a lager zone in the cylinder and reduce the wall quenching distance, these emissions decrease with the increase of hydrogen direct injection timing. The CO and HC emissions of 135°CA BTDC decrease by 41.5% and 71.4%, respectively, compared to 75°CA BTDC.

Cellulose nanocrystals (CNCs) is an exciting class of sustainable and carbohydrate material, which has great potential applications in molecular adsorption. However, the complex preparation process and limited adsorption capacity of CNCs hinder its commercial application. In this study, we design a novel functional cellulose nanocrystals-based adsorbent by an ingenious mixing of lignin-containing cellulose nanocrystals (LCNCs), sodium alginate (SA), and calcium chloride solution. Benefiting from the sulfonate groups of lignin, carboxyl groups of SA, the maximum adsorptive capability of LCNCs/SA beads for methylene blue was found to be 1181 mg g−1, which was significantly higher than previously reported biomass-based adsorbents. More importantly, LCNCs/SA beads can be reused several times. This strategy can not only improve the adsorption performance of CNCs-based materials, but also simplify the production technology of CNCs, which greatly promote the commercial application of CNCs materials.

A comparative study on effects of homogeneous or stratified hydrogen on combustion and emissions was presented for a gasoline/hydrogen SI engine. Three kinds of injection modes (gasoline, gasoline plus homogeneous hydrogen and gasoline plus stratified hydrogen) and five excess air ratios were applied at low speed and low load on a dual fuel SI engine with hydrogen direct injection (HDI) and gasoline port injection. The results showed that, with the increase of excess air ratio, the brake thermal efficiency increases firstly then decreases and reaches the highest when the excess air ratio is 1.1. In comparison with pure gasoline, hydrogen addition can make the ignition stable and speed up combustion rate to improve the brake thermal efficiency especially under lean burn condition. Furthermore, it can reduce the CO and HC emissions because of more complete combustion, but produce more NOX emissions due to the higher combustion temperature. Since, in the gasoline plus stratified hydrogen mode, the hydrogen concentration near the sparking plug is denser than that of homogeneous hydrogen, the ignition is more stable and faster, which further speed up the combustion rate and improve the brake thermal efficiency. In the gasoline plus stratified hydrogen mode, the brake thermal efficiency increases by 0.55%, the flame development duration decreases by 1.0°CA, rapid combustion duration decreases by 1.3°CA and the coefficient of variation (COV) decreases by 9.8% on average than that of homogeneous hydrogen. However, in the gasoline plus stratified hydrogen mode, due to the denser hydrogen concentration near the sparking plug and leaner hydrogen concentration near the wall, the combustion temperature and the wall quenching distance increase, which make the NOX and HC emissions increase by 14.3% and 12.8% on average than that of homogeneous hydrogen.

Zinc (Zn) is an essential trace element that modulate innate and acquired immune responses, and its deficiency triggers lymphopenia. However, the precise mechanisms underlying zinc-mediated lymphocyte maintenance have not been well clarified. Here, we have successfully generated a zip6-null mutant zebrafish line using TALENs. The Zip6-null mutant zebrafish developed normally during gastrulation. Loss of zip6 in zebrafish resulted in significant T lymphocyte reduction and a decrease in intracellular Zn levels. And the zip6 deficiency increases caspase-related cell apoptosis in both zebrafish cells and human T cells. Our results suggest that ZIP6 plays a critical part in T cell development, and enhance our understanding of Zn homeostasis and immune system maintenance.

Gabbroic rocks in continental arcs constrain the composition of sub-arc mantle and the roles played by mafic magmas in the generation and differentiation of continental crust. Here, we report whole-rock elemental and isotope (Sr and Nd) compositions of ~50 Ma and ~30 Ma gabbroic rocks from the central and eastern Gangdese (CG and EG) batholith, southern Tibet. A key observation is the along-arc isotopic and geochemical variations of ~50 Ma gabbros and dykes: EG rock samples show enriched Sr Nd isotope compositions, with initial 87Sr/86Sr = 0.7053–0.7077 and eNd(t) = −4.3 to +1.1 (average −3.0), and have higher abundance of heavy rare-earth elements (HREEs), high field strength elements, and melt-mobile elements compared with CG samples, which yield initial 87Sr/86Sr = 0.7038–0.7043 and eNd(t) = +3.4 to +6.9. Geochemical evidence suggests that the Sr Nd isotope differences reflect those in the mantle sources and are not due to crustal interactions, indicating that the sub-Gangdese batholithic mantle exhibited different degrees of enrichment at least ~50 Myr ago. These observations, combined with previous data, suggest that the sub-Gangdese batholithic mantle exhibited along-arc segmentation at 92°E–93°E at 50 Ma. This segmentation occurred probably between 90 and 47 Ma and was a result of the different characteristics and variable additions of the enriching agents into the asthenospheric mantle. CG gabbroic rocks were derived from depleted asthenospheric mantle enriched by variable amounts of aqueous fluids from the Neo-Tethyan slab, whereas EG rocks were generated from asthenospheric mantle enriched by hydrous melts from Indian continental crust. This interpretation implies that Indian continental crust was subducted beneath the southern Lhasa subterrane prior to 47 Ma. Compared with ~50 Ma rocks, EG ~30 Ma dykes exhibit higher melt-mobile element abundance and stronger REE fractionations, and were generated from deeper, melt-enriched mantle, signifying that a lithospheric thickening event occurred between 50 and 30 Ma in the EG batholith.

Hydrous ethanol has lower cost and energy consumption during the production process than anhydrous ethanol. Many researchers used hydrous ethanol instead of anhydrous ethanol to manufacture hydrous ethanol-gasoline. The water ratio in hydrous ethanol (ω) determines the energy consumption in the production process of ethanol. However, no one researched the effects of different ω on combustion and emissions of hydrous ethanol-gasoline. So, we prepared five kinds of ethanol with different ω (0, 5%, 10%, 15%, 20% vol.) to research the effects of ω on combustion and emissions. This study adopted combined injection with hydrous ethanol direct injection plus gasoline port injection (HEDI + GPI). The engine speed was 1500 rpm, and λ was 1, the intake manifold absolute pressure was 48 kPa, the direct injection ratio was 20%, five spark timings varied from 5 °CA BTDC to 25 °CA BTDC. The results showed hydrous ethanol prolonged flame development and propagation duration, decreased Tmax and Pmax, delayed APmax. Water increased COVimep, but using hydrous ethanol at the reasonable spark timing would not significantly affect the stability. Meanwhile, when the spark timing was MBT, compared with GE (gasoline/anhydrous ethanol dual fuel) fuel, as ω in GEW (gasoline/hydrous ethanol dual fuel) fuels increased, torque and brake thermal efficiency improved by 1.69%, 1.13%, −0.01%, −0.77%; HC increased by 2.13%, 9.02%, 23.89%, 37.15%; CO decreased by 41.95%, 28.56%, 5.59%, 2.46%; NOx decreased by 10.10%, −0.75%, −0.17%, 4.18%; total PN emissions decreased by 24.07%, 69.57%, 36.34%, 32.45%. Meanwhile, more water caused the size of particles to drop, made particles smaller.

Acetaminophen (APAP) overdose-induced hepatotoxicity is the most commonly cause of drug-induced liver failure characterized by oxidative stress, mitochondrial dysfunction, and cell damage. Therapeutic efficacy of omega-3 polyunsaturated fatty acids (n-3 PUFA) in several models of liver disease is well documented. However, the impacts of n-3 PUFA on APAP hepatotoxicity are not adequately addressed. In this study, the fat-1 transgenic mice that synthesize endogenous n-3 PUFA and wild type (WT) littermates were injected intraperitoneally with APAP at the dose of 400 mg/kg to induce liver injury, and euthanized at 0 h, 2 h, 4 h and 6 h post APAP injection for sampling. APAP overdose caused severe liver injury in WT mice as indicated by serum parameters, histopathological changes and hepatocyte apoptosis, which were remarkably ameliorated in fat-1 mice. These protective effects of n-3 PUFA were associated with regulation of the prolonged JNK activation via inhibition of apoptosis signal-regulating kinase 1 (ASK1)/mitogen-activated protein kinase kinase 4 (MKK4) pathway. Additionally, the augment of endogenous n-3 PUFA reduced nuclear factor kappa B (NF-κB) – mediated inflammation response induced by APAP treatment in the liver. These findings indicate that n-3 PUFA has potent protective effects against APAP-induced acute liver injury, suggesting that n-3 dietary supplement with n-3 PUFA may be a potential therapeutic strategy for the treatment of hepatotoxicity induced by APAP overdose.

Early Jurassic plutonic rocks from the Central Lhasa block that range from gabbro to granite yield similar 206Pb/238U ages ranging from 187.6 Ma to 196.0 Ma. Gabbros and diorites are characterized by similar radiogenic 87Sr/86Sr(t) ratios that range from 0.7053 to 0.7060, unradiogenic eNd(t) values ranging from −4.2 to −2.5 and eHf(t) values ranging from −8.8 to −2.8. Compared with the intermediate to mafic rocks, the granites have much higher 87Sr/86Sr(t) ratios, from 0.7102 to 0.7127, and lower eNd(t) values, from −8.7 to −7.5, and eHf(t) values from −11.9 to −7.5. Elemental and isotopic data suggest that the gabbros were derived from a melt-modified subarc mantle, diorites represent derivatives produced by hornblende fractional crystallization of gabbros, and granites were generated by the melting of ancient crustal basement rocks. Combined with literature data, these results suggest that the Central Lhasa block, as well as parts of the Southern and Northern Lhasa blocks, also contains ancient crystalline basement rocks.

Recent studies in the Xiaru and Malashan gneiss dome of the Tethyan Himalaya, southern Tibet identify that Xiaru and Paiku tourmaline-bearing leucogranite dike formed at ~ 28–29 Ma. Together with ~ 28 Ma Kuday garnet-bearing leucogranites, it is demonstrated that the Himalayan orogenic belt experienced a major episode of crustal melting in the Mid-Oligocene. Geochemical data indicate that three suites of leucogranite are characterized by large variations in the major and trace element compositions as well as Sr–Nd isotope systematics, which could be explained by combined fractional crystallization and relative contributions of micas and accessory phases dissolved into a crustal melt during decompressional melting of metapelitic rocks. Documentation of Oligocene partial melting of crustal rocks could indicate that the exhumation of deep crustal rocks in the Himalayan orogenic belt could have started as early as Oligocene.

Impregnated decorative paper was an important wood-based panel finishing material. However, traditional impregnated decorative paper was impregnated with melamine-formaldehyde resin, which will release formaldehyde and harm the human health. To solve this problem, small molecule polyacrylate-polyethylene glycol (PEG) adhesive was used to achieve the non-formaldehyde addition of the impregnation system. The dialdehyde modified CNF (D-CNF), modified by sodium periodate (NaIO4), and triethylenediamine were introduced to enhance the surface properties of the impregnated decorative paper. The results showed that the incorporation of D-CNF and triethylenediamine imparted excellent physical strength and surface properties to impregnated decorative paper. When the dosage of 0.3 wt% D-CNF and 3 mL/100 g triethylenediamine in the compound emulsion, the hardness, abrasion resistant value and surface bonding strength of impregnated decorative paper adhered fiberboard reached 3H, 330 r of damage and 1.13 MPa, respectively. Thus, it could be effectively used for making high-performance formaldehyde-free impregnated decorative paper.

In this paper, on the basis of combined injection technique, three injection modes with five n-butanol/gasoline volume ratios ( ν N ) were put forward, aiming to compare and evaluate the relationship between the injection mode and the combustion and emission characteristics of an n-butanol/gasoline SI engine equipped with an extra hydrogen direct injection system. The results indicated that under low load condition, compared with NGP (n-butanol/gasoline port injection) mode, the NGPD (n-butanol/gasoline combined injection) mode and NGPH (n-butanol/gasoline with hydrogen combined injection) mode can both improve the combustion performance. The peak cylinder pressure of NGPD and NGPH mode was 5.58% and 11.63% higher than that of NGP mode on average, respectively. Furthermore, the combined injection modes concentrated the process of heat release, shortened the combustion duration, increased the power performance and improved the combustion stability at all ν N . As for emissions, the NGPD and NGPH combined modes significantly decreased the HC and CO emissions, but increased the NOX emissions. Among all the test conditions, the NGPH mode with 25% ν N obtained the best combustion quality. Additionally, the effect rules of ν N on combustion and emission characteristics under NGP mode were found to be consistent with those under NGPD and NGPH combined modes.

We report on the fabrication of Nd:YCa4O(BO3)3 (Nd:YCOB) ridge waveguides by combining carbon ion irradiation and precise diamond blade dicing. The guiding and spectroscopic properties of the planar as well as ridge waveguides are investigated. The second harmonic generation (SHG) at 532 nm has been realized through the waveguide structures. With nearly the same input power, the maximum average output powers are 0.56 mW and 0.62 mW, and the maximum conversion efficiencies reach 0.3%W−1 and 0.5%W−1, for planar and ridge waveguides, respectively.

Split hydrogen direct injection is proved to be a better way to use the hydrogen in the engine. Therefore, a numerical study on effects of split injection proportion on hydrogen mixture distribution, combustion and emissions was presented of a gasoline/hydrogen SI engine with split hydrogen direct injection to investigate the principle of split hydrogen direct injection. Under lean burn condition, six different split injection proportions achieve six kinds of hydrogen mixture distribution, which affect the engine performance a lot. With split hydrogen direct injection, the mixture nearby the spark plug is denser and in other zone is more homogeneous at the same time, which achieve better performances of both efficiency and emissions. As the first injection proportion increases, the cylinder pressure climbs to the highest with first injection proportion of 33% and the NOX, CO and HC emissions decrease continually. When the first injection proportion is 75%, the NOX, CO and HC emissions are respectively 31.6%, 79.3% and 40.6% less than those of single hydrogen direct injection.

Recently, more attention has been paid to the application of biobutanol in spark ignition (SI) engines due to its superior properties among the biofuels. However, the high energy consumption and low efficiency of recovering biobutanol from ABE solution during the fermentation process lead to the high price of biobutanol, which limits its popularization in vehicles. Using ABE directly can solve the problem of high price of bio-butanol. This research explored the performance of an SI engine with ABE port injection (ABEPI) plus gasoline direct injection (GDI) at different excess air ratio (λ = 0.9, 1.0, 1.1, 1.2) and ABE port injection ratio (ABEPIr = 0, 25%, 50%, 75%, 100%). The results show that CA10-90 declines with increasing ABEPIr. CA0-10 and CA0-90 decrease with ABEPIr increasing at λ = 0.9, and first descend and then rise at λ = 1.0, 1.1 and 1.2. The coefficient of variations of IMEP (CoVIMEP) reaches the minimum value at ABEPIr = 75%. As ABEPIr increases, the peak in-cylinder pressure (Pmax), indicated mean effective pressure (IMEP) and brake thermal efficiency (BTE) increase at λ = 0.9 while first increase and then decrease at λ = 1.0, 1.1 and 1.2, reaching the maximum values at ABEPIr = 75%. Hydrocarbon (HC) reaches the minimum value at ABEPIr = 50%. Particle number decreases dramatically as ABEPIr increases from 0% to 50% and remains at an extremely low level when ABEPIr is greater than 50%. In summary, ABE is suitable for SI engine as an alternative fuel and fuels with high ABE ratio (≥50%) can effectively improve the combustion and particle emissions by ABEPI + GDI combined injection.

In this paper, a numerical research on an n-butanol ignition engine with hydrogen direct injection was carried out, aiming to observe the effect of hydrogen blending fractions on idling performance. A three-dimensional dynamic mesh model coupled with a detailed chemical kinetic mechanism of n-butanol oxidation were established to investigate the engine combustion process in CFD software CONVERGE. And the numerical model was validated through experiments. The performance of pressure and temperature inside cylinder, HC and CO emissions and formaldehyde and acetaldehyde emissions with four hydrogen fractions were simulated and analyzed. The simulation results showed that in comparison with pure n-butanol, the peak cylinder pressure increased 18.62%, 22.86% and 25.41% at φ H 2 = 5%, φ H 2 = 10% and φ H 2 = 15%, respectively. Meanwhile, the process of heat release can be accelerated and concentrated by hydrogen blending. The HC and CO emissions decreased gradually with the increase of hydrogen fraction. The largest magnitude of reduced HC and CO emissions was at φ H 2 = 5% as 31.31% and 19.05%, respectively. In terms of unregulated emissions, the acetaldehyde emissions remained a higher level than formaldehyde emissions for all hydrogen fractions at idle condition, and both decreased with the increase of hydrogen fraction. The distribution of formaldehyde and acetaldehyde concentration were closely related to the temperature field inside cylinder. The improvement of acetaldehyde emissions affected by adding hydrogen was more significant than that of formaldehyde emissions. Through hydrogen direct injection, a local hydrogen-enriched area near the spark plug can be formed, which contributed to better combustion performance of n-butanol engine at idle condition.

In order to reach the goal of energy conservation and pollution emissions reduction, the combustion and emissions of a combined injection engine with ethanol port injection and gasoline direct injection under lean burn conditions are investigated in this paper. The experiments are carried out by using different direct injection timing (DIT), gasoline addition ratio (αgasoline) and excess air ratios (λ). The results indicate that Tmax declines after gasoline addition at λ = 1, 1.2, while increases after gasoline addition at λ = 1.4. The IMEP reaches the maximum value at DIT = 90 or 105 °CA BTDC and 0%, 10% and 30% gasoline addition bring the highest IMEP at λ = 1, 1.2 and 1.4, respectively. The COVIMEP decreases continuously with the increase of αgasoline and the EPI+GDI mode has great advantages in improving the combustion stability under λ = 1.4 condition. As for gaseous emissions, from λ = 1 to λ = 1.4, HC emissions change from increasing trend to the decreasing trend with the increase of αgasoline, while the NOx emissions show the opposite. As for particle number, at λ = 1 and 1.2, the total particle number (TPN) shows an upward trend with the increase of αgasoline. When λ = 1.4, TPN decreases with the increase of αgasoline.

Cellulose nano-crystals (CNC) have attracted great interests as a novel nanostructured material in recent years, thanks to their excellent mechanical properties, high surface area and lightweight and biocompatibility etc. Due to its low charged group content, CNC prepared from the hydrochloric acid hydrolysis has poor dispersibility in water, which hinders its further applications. In this work, well-dispersed cellulose nano-crystals are successfully prepared using a two-step method, consisting of hydrochloric acid hydrolysis, followed by adsorption of hexadecyl trimethyl ammonium bromide (CTAB) onto CNC. Results show that CTAB at a low concentration (0.13–0.47 mM) provides effective steric barriers to minimize the CNC aggregation, which is supported by TEM images and particle size distribution of CNC. At high CTAB concentrations (>0.5 mM), CNC aggregation occurs, which is due to the “bridging” effect of CTAB.

Extraction of hemicelluloses is a primary step in the conversion of plant biomass to valuable biofuels and chemicals. Hemicellulose is distributed in the fiber cell wall, and the compact structure of the fiber cell wall barricades the transport of hemicelluloses in the extraction process. In this paper we presented a novel microwave-assisted extraction process enhanced with an enzymatic pretreatment to improve the hemicelluloses extraction rate from bagasse. Experimental results showed that the enzyme dosage, alkali concentration and microwave irradiation time were main factors governing the yield of hemicellulose. The optimal conditions of the enzymatic pretreatment were: enzyme dosage of 138 IU/g bagasse and irradiation time of 30 min. Under these conditions, 86% of the hemicellulose in bagasse was extracted. After the enzymatic pretreatment the surface area of bagasse increased significantly which facilitated the subsequent microwave-assisted extraction process.

The 6061 semi-solid aluminium alloy feedstocks prepared by near-liquidus casting were compressed in semi-solid state by means of Gleeble-3500 thermal-mechanical simulator. The relationship between the true stress and the true strain at different temperatures and strain rates was studied with the deformation degree of 70%. The microstructures during the deformation process were characterized. The deformation mechanism and thixo-forming properties of the semi-solid alloys were analyzed. The results show that the homogeneous and non-dendrite microstructures of semi-solid 6061Al alloy manufactured by near-liquidus casting technology could be transformed into semi-solid state with the microstructure suitable for thixo-forming which are composed of near-spherical grains and liquid phase with eutectic composition through reheating process. The deformation temperature and strain rate affect the peak stress significantly rather than steady flow stress. The resistance to deformation in semi-solid state decreases with the increase of the deformation temperature and decrease of the strain rate. At steady thixotropic deformation stage, the thixotropic property is uniform, and the main deformation mechanism is the rotating or sliding between the solid particles and the plastic deformation of the solid particles.

The purpose of this study is to investigate the effects of flavonoid, isolated from aerial parts of Scutellaria baicalensis Georgi (SSF), on memory deficits, neuronal degeneration and abnormal energy metabolism induced by permanent global ischemia in rats. The global ischemia was produced in female Sprague-Dawley rats by permanent occlusion of the bilateral common carotid arteries. The permanent global ischemia in rats resulted in a significantly increased latency of the rat to find the hidden platform and a decreased swimming distance from the target quadrant in the Morris water maze task. The pathological changes in the neurons of ischemic rats, observed in the hippocampus and cerebral cortex, included neuron loss, neuron swelling, nuclear shrinkage or disappearance, neuronophagia and reduced density of Nissl bodies in the neuron. Moreover, the levels of lactate and ATPase activity in ischemic rats were notably increased and decreased, respectively, in the hippocampus and cerebral cortex as compared with sham-operated rats. Daily oral administration of SSF (35 mg/kg, 19-20 days) dramatically reduced the decrease in learning and memory, attenuated neuronal injury and improved abnormality of energy metabolites in rats induced by global ischemia. These findings suggest that SSF may be beneficial for the treatment of vascular dementia.