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Due to radical resection, endoprosthetic reconstruction (EPR) is more invasive and increases the risk of dislocation. Therefore, the suitability of EPR for elderly patients with metastatic tumor needs further investigation.Seventy-one adult patients with isolated proximal femoral bone metastases who underwent EPR were retrospectively analyzed and stratified into two groups: elderly age group (≥60 years, n = 31) and younger age group (60 years, n = 40). The effect of age on prognosis was analyzed to determine whether EPR is beneficial in elderly patients with proximal femoral metastatic tumor. Cox regression modeling was used to evaluate the effect of different factors on postoperative survival outcomes.Ten (32.26%) and 9 (22.50%) cases of perioperative complications were recorded in the elderly and younger age groups, respectively, with median survival times of 22.00 ± 4.61 months and 23.00 ± 2.85 months, respectively; a log-rank test showed that the difference was not statistically significant (p = 0.657). A Cox regression model was established with patient age as the covariable to evaluate whether it affected postoperative survival. The risk of death due to age was not significant (p = 0.649), but malignancy and femoral metastasis type were significantly associated with postoperative survival (p = 0.001 and p = 0.019).Although older patients have a slightly higher incidence of postoperative complications than younger patients, they do not experience severe adverse consequences. With rigorous selection and careful preparation, EPR is appropriate for the treatment of proximal femoral metastases in older patients, including those with Harrington type I-II acetabular invasion.

The Late Pliocene–Early Pleistocene is an important transitional period in the Cenozoic evolution of global climate and environment. Previously, we demonstrated the occurrence of distinct cycles in vegetation and climate in the Nihewan Basin, during 2.89–1.78 Ma. However, the specific cycles and their forcing mechanisms were not studied more in-depth. Here we present the results of wavelet and spectral analyses of pollen percentages (Picea, Pinus, xerophytic taxa and broadleaved trees), macro-charcoal concentration, clay % and sand %, and magnetic susceptibility of 340 samples from the NHA drill core in the Nihewan Basin, during 2.89–1.78 Ma. The results reveal dominant ~20-kyr and ~40-kyr cyclicities: the pollen percentages of Pinus and broadleaved trees, magnetic susceptibility, and clay %, indicating a warm and humid climate, are more significantly influenced by ~20-kyr; in contrast, the percentages of Picea and xerophytic taxa, macro-charcoal concentration, and sand %, associated with a cold and dry climate, are mainly influenced by ~40-kyr. The ~20-kyr and ~40-kyr cycles corresponding to the dominant cycles of the East Asian summer monsoon and winter monsoon, which are respectively driven by Earth orbital precession and tilt, indicating that vegetation and climate change in the Nihewan Basin during 2.89–1.78 Ma was forced by a combination of low- and high-latitude processes. Otherwise, most of the proxy indexes also show a pronounced ~100-kyr cycle, which may be a response to changes in Northern Hemisphere ice sheets, emphasizing the importance of high-latitude forcing of vegetation and climate change in the Nihewan Basin.

H-Beta zeolites were employed for hexose decarburization to furfural. Excellent performance was achieved over high-Si H-Beta zeolite due to its high B/(B + L) ratio. The synergetic mechanism between *BEA channel and framework-Al is decisive.

Combining glucose dehydration and the subsequent hydrogenation in one pot is a preferable approach for process development as such a method allows in situ generation of the reactive intermediate to undergo further reaction without extra energy-intensive separation. Herein, phosphotungstic acid and various types of titania (anatase, rutile, P25) supported Ru-based catalysts were considered as the dehydration and hydrogenation catalysts, respectively. Modulating the different reactant media (N2, H2), various products were obtained with GBL–H2O as the solvent. A considerable yield (42%) of levulinic acid (LA) and γ-valerolactone (GVL) (40%) were obtained in nitrogen and subsequent hydrogen. Ru/TiO2 (rutile) was the favorable hydrogenation catalyst among the three types of Ru/TiO2. Meanwhile, a certain amount of sorbitol (36%) was obtained in pure hydrogen. The hydrogenation of glucose is more likely to occur than the glucose dehydration. The physicochemical properties of the catalysts were characterized by XRD, BET, TPR, STEM and in situ CO/FT-IR, and the results show that well-dispersed Ru particles are located on the rutile crystallites, which facilitated the hydrogenation of LA. A strong metal support interaction (SMSI) was responsible for the various microstructure properties and the different hydrogenation reactivity. This work allows a better understanding of the reaction paths of glucose conversion.

Using all the data of the High Energy X-ray Timing Experiment (HEXTE) on board the Rossi X-ray Timing Explorer for Scorpius X-1 from 1996 February to 2012 January, we systematically search for hard X-ray tails in the X-ray spectra in 20–220 keV and, together with the data of the Proportional Counter Array (PCA), investigate the evolution of the detected hard X-ray tails along the Z-track on its hardness-intensity diagram (HID). The hard X-ray tails are detected in 30 observations and their presence is not confined to a specific position on the HID. Our analysis suggests that from the horizontal branch (HB), through the normal branch (NB), to the flaring branch (FB) on the HID, the hard X-ray tail becomes hard and its flux decreases. Jointly fitting the PCA+HEXTE spectra in 3–220 keV, it is found that the Bulk-Motion Comptonization (BMC) could be an alternative mechanism for producing the hard X-ray tails on the HB and the NB of this source. The temperature of the seed photons for the BMC spans in the range of ∼(2.4–2.6) keV, indicating that the seed photons might come from the surface of the neutron star (NS) or the boundary layer and, therefore, the BMC process could take place around the NS or in the boundary layer. Some possible mechanisms for producing the hard X-ray tails on the FB are given.

Ningjinpo paleolake was the largest lake in the North China Plain during the Holocene, and its continuous sedimentary record has the potential to reconstruct the summer monsoon intensity and determine the limnological response to abrupt climatic events at a high resolution. Here we use AMS 14C dating and analyses of grain-size and major element contents, and the results show that: (1) During 11.5–10.0 cal kyr BP, the geochemical climate change index (C) (1.16), sediment accumulation rate (SAR) (0.007 cm/yr) and median particle diameter (Md) (20.6 μm) are the lowest within the section, while the geochemical drought index (0.0323), Fe/Mn ratio (0.0088) and clay content (17.3%) are the highest, which indicate that the North China Plain received less precipitation, and chemical weathering and erosional intensity in the Ningjinpo paleolake catchment were weak. (2) During 10.0–7.7 cal kyr BP, the C index (1.36), content of sand (19.1%) and silt (68.0%), Md (27.2 μm) and SAR (0.019 cm/yr) increase significantly. These characteristics indicate that the climate gradually became wetter, chemical weathering and erosion intensity increased, and there was increased runoff to the lake, which raised the lake level. (3) During 7.7–5.5 cal kyr BP, the C index (1.56), silt content (71.8%) and SAR (0.030 cm/yr) increase to the highest, while the Fe/Mn ratio (0.0068), sand content (14.4%) and Md (21.4 μm) decrease to their lowest levels. These suggest the climate was warm and humid, the runoff to the lake was large, chemical weathering in the catchment was strong, and the water level of the lake reached the maximum for the Holocene. (4) During 5.5–3.3 cal kyr BP, the C index (1.26) and SAR (0.011 cm/yr) decrease substantially, whereas the sand content (28.2%) and Md (18.3 μm) increase to the highest levels. These characteristics demonstrate that the climate gradually became arid, the runoff to Ningjinpo paleolake was reduced, the intensity of chemical weathering and erosion in the catchment weakened, and the lake level decreased, although the high frequency of floods in this period. (5) In addition to the globally-recorded abrupt climatic events at ~8.2 cal kyr BP, ~5.3 cal kyr BP and ~4.2 cal kyr BP, which were recorded in the northern monsoon region of China, an abrupt climatic event in the middle Holocene, at ~7.2 cal kyr BP, was also recorded. In the northern monsoon region of China, these events may have been amplified by unusually active ENSO since the middle Holocene.

Here we report the spectral-timing results of the black hole X-ray binary 4U 1630–47 during its 2021 outburst using observations from the Hard X-ray Modulation Telescope (Insight-HXMT). Type C quasi-periodic oscillations (QPOs) in ∼1.6–4.2 Hz and quasi-regular modulation (QRM) near 60 mHz are detected during the outburst. The mHz QRM has a fractional rms of ∼10%–16% in the 8–35 keV energy band with a Q factor (frequency/width) of ∼2–4. Benefiting from the broad energy band of Insight-HXMT, we study the energy dependence of the ∼60 mHz QRM in 1–100 keV for the first time. We find that the fractional rms of the mHz QRM increases with photon energy, while the time lags of the mHz QRM are soft and decrease with photon energy. Fast recurrence of the mHz QRM, in a timescale of less than 1 hr, has been observed during the outburst. During this period, the corresponding energy spectra moderately change when the source transitions from the QRM state to the non-QRM state. The QRM phenomenon also shows a dependence with the accretion rate. We suggest that the QRM could be caused by an unknown accretion instability aroused from the corona.

HZSM-5, Hβ, HY and USY zeolites were applied to the isomerization of glucose. An excellent selectivity (96%) of fructose was achieved, catalyzed by HY zeolite in gamma-butyrolactone/H2O over the fixed bed reactor. Moreover, the glucose isomerization could be carried out for over 480 h under the optimal conditions. High density of Lewis acid (0.27 mmol·g−1) over HY facilitates the intramolecular C2 → C1 H-shift reaction over the glucopyranose ring, which is the rate-determining step during Lewis acid-catalyzed steps of the glucose isomerization. Besides, large porous structure of HY zeolite (7.4 A) facilitates the isomerization of glucose.

The selective synthesis of furfural or hydroxymethylfurfural (HMF) from fructose on single catalyst (Beta zeolite, Hβ) is challenging task. However, in this study, selectivity of Hβ zeolite was discovered easily to tune by solvent effects. Strong solvent effects on the selectivity of fructose conversion were observed in different manners depending on the solvent used. It was shown that the coordinated state of framework aluminum, induced by solvent effects, has a major impact on the selectivity. The solvents with amide group were discovered to induce the reversible tetrahedral-octahedral framework aluminum transformation, but the configuration of aluminum was no influenced by other solvents such as γ-butyrolactone (GBL). Compared with other solvents, the GBL was not able to enhance turnover frequency (TOF) value of reaction but also suppress the degradation of furfural. Interestingly, a considerable yield of furfural (50.25%) was obtained combined with tetrahedral and octahedral framework aluminum active sites in GBL, while high selectivity of HMF (83.3%) was achieved in presence of single tetrahedral framework aluminum over Hβ in NMP.

Novel Cu/ZnO-Al2O3 composites had been constructed and applied in furfural hydrogenation to produce furfuryl alcohol in a fixed-bed reactor. As the result, conversion of FFA over Cu/ZnO catalyst (within 16–24 h TOS) could be improved from 84.9% to 98.0% at 120 °C and 51.4% to 72.1% at 100 °C with a high selectivity of FOL (≈98%) over the novelly constructed Cu/ZnO-Al2O3 catalyst. The role of Al components derived from different precursors like Al(NO3)3, as-prepared Al(OH)3 and pseudo-boehmite had been systemically investigated by various techniques such as XRD, Raman spectroscopy, H2-TPR, N2O titration, XPS, AES experiments and confirmed to be both improving dispersion of copper/zinc species and hindering Cu-ZnO interaction of the aurichalcite derived catalysts. Preparation of the industrial Cu/ZnO-Al2O3 catalysts had been revealed and explained more clearly.

Transient numerical calculations were carried out to predict the evolutions of temperature and thermal stress in sapphire single crystal during the cooling process by heat exchanger method (HEM). Internal radiation in the semitransparent sapphire crystal was taken into account using the finite volume method (FVM) in the global heat transfer model. The numerical results seem to indicate that the narrow bottom region of the sapphire crystal is subjected to high thermal stress during the cooling process, which could be responsible for the seed cracking of the as-grown crystal, while the thermal stress is relatively small in the central main body of the crystal, and is less than 10 MPa during the whole cooling process. The fast decrease of the thermal stress in the bottom region of the crystal during the initial stage of cooling process is dominated by the reduction of the cooling helium gas in the heat exchanger shaft, and is not significantly affected by the heating power reduction rate.

The status of the ZIKV outbreak, including the epidemiology, transmission, clinical presentation, complications, laboratory diagnosis, clinical diagnosis, differential diagnosis, treatment and control measures, were reviewed to present a better understanding of ZIKV.

Selective conversion of fructose to fuels and fine chemicals is an important step for biomass utilization. In this paper, direct conversion of fructose to 2,5-dihydroxymethylfuran and 2,5-dimethylfuran was first realized over combined HY zeolite and inexpensive hydrotalcite (HT)-Cu/ZnO/Al2O3 in a fixed-bed reactor. The cooperative effect of HY zeolite and γ-butyrolactone solvent facilitated the dehydration of fructose into 5-hydroxymethylfurfural. By adjusting the hydrogenation temperature for HMF over HT-Cu/ZnO/Al2O3 catalyst, high yields of 2,5-dihydroxymethylfuran (48.2%) at 140 °C and 2,5-dimethylfuran (40.6%) at 240 °C were obtained, respectively.

An efficient process was designed for the synthesis of furfuryl alcohol and 2-methylfuran from xylose using a continuous fixed-bed reactor over a catalyst combining Hβ zeolite and Cu/ZnO/Al2 O3 in γ-butyrolactone (GBL)/water as solvent. The cooperative effect of Hβ zeolite and GBL facilitated the dehydration of xylose and enhanced largely the furfural yield. The production of furfuryl alcohol and 2-methylfuran can be simply tuned by changing the hydrogenation temperature for furfural over the Cu/ZnO/Al2 O3 catalyst. The yield for furfuryl alcohol reached 87.2 % at 150 °C whereas a yield of 86.8 % was achieved for 2-methylfuran at 190 °C.

Influences of drying air temperature, radiation distance, slice thickness and wavelength on drying time, energy consumption, and product quality (color, shrinkage, rehydration and total saponin) were investigated in combined infrared and hot air impingement drying (IR-HAD). Results illustrated that temperature and slice thickness were the most distinct factors affecting the drying time. Moisture effective diffusivity decreased with decrease in moisture content, and was influenced by drying conditions. Radiation distance significantly affected rehydration capability, while temperature and thickness affected almost all quality attributes. Drying caused an insignificant reduction in total saponin, and similar volume shrinkage results were found due to constant amount of water removed. Thickness of 6 mm maintained better quality than thicker bodies, coincidence with the calculated infrared penetration depth (5.30–7.25 mm). IR-HAD at wavelength of 2–4 μm increased drying rate slightly than that at 0.25–2 μm, while insignificant difference in product quality. Particularly, IR-HAD samples showed smaller thickness shrinkage and larger area shrinkage, as opposed to hot air drying. IR-HAD offered many advantages in minimizing the drying time and better preserving the quality over hot air drying under the same conditions, but markedly enhanced the specific energy consumption. This study proves that IR-HAD is a suitable technique that retains quality characteristics of vegetables.

At the end of 2018, the Southwest Power Grid will asynchronously interconnect with the State Grid, and the tests show that it exists a high proportion of ultra-low frequency oscillation (ULFO), which threatening the operation of system. Based on the governor system model, the negative damping mechanism of ULFO is analyzed, and the suppression measure of adjusting the PI parameters of governor system is given. The details are as follows: in this paper, the phenomenon of ULFO in the Southwest Power Grid is introduced. And then based on detailed model, the mechanical damping coefficient of the governor system of each generator under the ultra-low frequency is calculated. The results show that the negative damping provided by hydro-turbine governor system is one of the main reasons causing the oscillation. Furthermore, the impact of PI parameters of governor system on the damping characteristics of hydropower generators is analyzed. Moreover, the idea to suppress ULFO based on adjusting the PI parameters is given, together with the considering for the influence of parameters on the transient and steady-state characteristics. Finally, simulation results show that the proposed PI parameters adjusting method to governor system could suppress the ULFO.

The ultra-low frequency oscillation (ULFO) is found in the future Southwest Power Grid under some faults, which will asynchronous interconnect with the State Grid via the HVDC and VSC-HVDC at the end of the 2018. This paper introduces the phenomenon of ultra-low frequency oscillation of asynchronous interconnection in Southwest Power Grid and analyzes the characteristics of ultra-low frequency oscillation with measurement data. In details, the energy flow calculated with the measure data is used to evaluate the contribution of each unit to the ultra-low frequency oscillation and locate disturbance sources of the oscillation. Meanwhile, the amplitude-phase characteristic for the oscillation at the different power plant is used to identify that the oscillation is mainly manifests between the hydropower units and the thermal power units. Furthermore, the damping characteristics of the excitation and governor system analysis reveals that the main factor of the oscillation is the lack of the damping or negative damping characteristic of the hydro-turbine governor systems.

With the observations from \textit{Rossi X-ray Timing Explorer}, we search and study the X-ray bursts of accreting millisecond X-ray pulsar SAX~J1748.9-2021 during its 2010 outburst. We find 13 X-ray bursts, including 12 standard type-\uppercase\expandafter{\romannumeral1} X-ray bursts and an irregular X-ray burst which lacks cooling tail. During the outburst, the persistent emission occurred at $\sim$(1-5)$\%\rm {\dot{M}_{Edd}}$. We use a combination model of a blackbody (BB), a powerlaw, and a line component to fit the persistent emission spectra. Another BB is added into the combination model to account for the emission of the X-ray bursts due to the thermonuclear burning on the surface of the neutron star. Finally, we modify the combination model with a multiplicative factor $f_{\rm a}$, plus a BB to fit the spectra during the X-ray bursts. It is found that the $f_{\rm a}$ is inversely correlated with the burst flux in some cases. Our analysis suggests that the ignition depth of the irregular X-ray burst is obviously smaller than those of the type-\uppercase\expandafter{\romannumeral1} X-ray bursts. We argue that the detected type-\uppercase\expandafter{\romannumeral1} X-ray bursts originate from helium-rich or pure-helium environment, while the irregular X-ray burst originates from the thermonuclear flash in a shallow ocean., 12 pages, 7 figures, Accepted for publication in Astrophysics and Space Science

The ultra-low frequency oscillations(ULFO) are found in the future Southwest Power Grid under some faults, which will asynchronously interconnect with the State Grid via the HVDC and VSC-HVDC before the end of 2018. In this paper, the phenomenon of ULFO in the asynchronous interconnected Southwest Power Grid is introduced. And then, with the oscillation energy flow and the amplitude-phase analysis for the ULFO, the energy characteristics of each power plant participating in ULFO are revealed, i.e., the ULFO are mainly between the hydropower plants and the thermal power plants. Furthermore, with the analysis of damping characteristics of main hydropower plants, the cause of the ULFO, i.e., lacking of damping in the hydropower plant is revealed. Upon the above results, an example of suppressing the ULFO with the approach of control parameters tuning for the governor of the dominant generators is presented.

Eight pulsars have low braking indices, which challenge the magnetic dipole braking of pulsars. 222 pulsars and 15 magnetars have abnormal distribution of frequency second derivatives, which also make contradiction with classical understanding. How neutron star magnetospheric activities affect these two phenomena are investigated by using the wind braking model of pulsars. It is based on the observational evidence that pulsar timing is correlated with emission and both aspects reflect the magnetospheric activities. Fluctuations are unavoidable for a physical neutron star magnetosphere. Young pulsars have meaningful braking indices, while old pulsars' and magnetars' fluctuation item dominates their frequency second derivatives. It can explain both the braking index and frequency second derivative of pulsars uniformly. The braking indices of eight pulsars are the combined effect of magnetic dipole radiation and particle wind. During the life time of a pulsar, its braking index will evolve from three to one. Pulsars with low braking index may put strong constraint on the particle acceleration process in the neutron star magnetosphere. The effect of pulsar death should be considered during the long term rotational evolution of pulsars. An equation like the Langevin equation for Brownian motion was derived for pulsar spin-down. The fluctuation in the neutron star magnetosphere can be either periodic or random, which result in anomalous frequency second derivative and they have similar results. The magnetospheric activities of magnetars are always stronger than those of normal pulsars., 12 pages, accepted for MNRAS

Using all the observations from Rossi X-ray Timing Explorer for Z source GX 349+2, we systematically carry out cross-correlation analysis between its soft and hard X-ray light curves. During the observations from January 9 to January 29, 1998, GX 349+2 traced out the most extensive Z track on its hardness-intensity diagram, making a comprehensive study of cross-correlation on the track. The positive correlations and positively correlated time lags are detected throughout the Z track. Outside the Z track, anti-correlations and anti-correlated time lags are found, but the anti-correlated time lags are much longer than the positively correlated time lags, which might indicate different mechanisms for producing the two types of time lags. We argue that neither the short-term time lag models nor the truncated accretion disk model can account for the long-term time lags in neutron star low mass X-ray binaries (NS-LMXBs). We suggest that the extended accretion disk corona model could be an alternative model to explain the long-term time lags detected in NS-LMXBs., 24 pages, 5 figures, accepted for publication in Monthly Notices of the Royal Astronomical Society

An aqueous suspension of WO3/poly(4-(2,3-dihydrothieno[3,4-b]-[1,4]dioxin-2-yl-methoxy)-1-butanesulfonic acid) (PEDTS) hybrid nanoparticles (NPs) is prepared by air-assisted oxidative polymerization and simultaneous attachment of PEDTS on WO3-NPs, and used for electrochromic (EC) film fabrication via air-brush spraying. The hybrid EC device exhibits enhanced EC properties compared to the ones based on WO3-NP or PEDTS alone.

Cu/SiO2 catalysts were synthesized by different methods, which greatly influenced their texture and the catalytic performance. The AE-Cu/SiO2 catalyst was prepared via the ammonia evaporation method and showed a 95.5% yield for 2-methylfuran (a promising fuel additive) because of the cooperative effects of surface Cu0, Cu+ species and acid sites, which respectively stemmed from the reduction of highly dispersed CuO species, copper species that fiercely interacted with the support SiO2, and the special structure. The ammonia evaporation method favored the formation of a copper phyllosilicate phase with a lamellar structure, which could provide a large number of Cu nanoparticles and acid sites and further improve the activity and selectivity. Crucially, the stability of the AE-Cu/SiO2 catalyst (>210 h) was also significantly improved due to the enhanced copper–silicon interactions, which could immobilize copper particles and resist the fast transmigration (aggregation and loss) of copper particles in the thermal treatment process. In contrast, the CP-Cu/SiO2 catalyst was synthesized via the conventional precipitation method and presented poor activity and stability toward 2-methylfuran because of large copper particles, severe aggregation and a loss of copper species during reaction. Compared with the conventional CP-Cu/SiO2 catalyst, the use of the AE-Cu/SiO2 catalyst in the synthesis of the biofuel 2-methylfuran could not only improve the yield of the desired product, but also decrease by at least 20 °C the reaction temperature which is propitious for prolonging the lifetime of the Cu/SiO2 catalyst.

A series of Pd/Al2O3 catalysts with different alkali earth metals (Mg, Ca, Sr, Ba) and varying Sr loadings (1.8, 3.5, 5.3, 7 and 8.8 wt%) were investigated for 5-hydroxymethylfurfural (HMF) decarbonylation. The alkali earth metal and content were demonstrated to have profound influences on the metal dispersion, electron density of the metal, acid–base properties of the catalyst, and catalytic performance. The Pd3Sr/Al2O3 catalyst exhibited the highest initial activity and furfuryl alcohol selectivity, achieving a yield of 92%. The key to high decarbonylation selectivity is the suppression of hydrogenolysis and etherification side reactions through the attenuation of the acidity of catalysts. Successful catalytic activity not only lies in the increased metallic surface area, but is also affected by the adsorption properties of the carbonyl group and the poisoning CO produced. The catalytic activity is linearly correlated to the surface metallic area at low modifier loading over PdM/Al2O3 catalysts. But along with further increased metallic surface area over PdXSr/Al2O3, HMF conversion initially increased, reaching a plateau over Pd3Sr/Al2O3 and then decreased with increasing Sr loading. A synergistic effect between the Sr species and metallic Pd was proposed, which promoted the migration of carbonyl adsorption from the support to the surface Pd through the electron donation of Sr species to Al2O3 and metallic Pd.

Selective hydrogenation of 5-hydroxymethylfurfural (HMF) is of great importance for future energy and chemical supply. Herein, we propose for the first time that non-noble Ni-Al2O3 catalysts derived from hydrotalcite-like compounds can efficiently and selectively convert HMF into 2,5-dimethylfuran (DMF), 2,5-dimethyltetrahydrofuran (DMTHF) and 2,5-dihydroxymethyltetrahydrofuran (DHMTHF). Homogeneous elemental distributions of the hydrotalcite-like precursor facilitate good dispersion of Ni and Al2O3 species and strong interaction between them over the resulting catalysts. The catalysts therefore exhibited superior reactivity. Through fine modulation of surface metal–acid bifunctional sites and control of reaction conditions, high yields of DMF (91.5%), DMTHF (97.4%) and DHMTHF (96.2%) can be diversely achieved. The results demonstrate the feasibility of Ni catalysts for selective hydrogenation of CO, CC and C–O bonds, which have great potential for biomass utilization.

Selective conversion of 5-hydroxymethylfurfural (HMF) can produce sustainable fuels and chemicals. Herein, Cu–ZnO catalysts derived from minerals (malachite, rosasite and aurichalcite) were employed for selective hydrogenation of HMF for the first time. High yields of 2,5-dihydroxymethylfuran (~99.1%) and 2,5-dimethylfuran (~91.8%) were obtained tunably over the catalyst with a Cu/Zn molar ratio of 2, due to the well-dispersed metal sites tailored by mineral precursors, well-controlled surface sites and optimized reaction conditions. The relationship between catalytic performance and catalyst properties was elucidated by characterization based on the composition and the structural and surface properties, and catalytic tests. The catalyst can also be extended to selective hydrogenation of other bio-derived molecules (furfural and 5-methylfurfural) to target products. The construction of mineral-derived Cu–ZnO catalysts and the revelation of the structure–performance relationship can be applied to further rational design and functionalization of non-noble Cu catalysts for selective conversion of bio-derived compounds.

With Rossi X-ray Timing Explorer (RXTE) data, we systematically study the cross-correlation and time lag in all spectral states of black hole X-ray binary (BHXB) XTE J1859+226 in detail during its entire 1999-2000 outburst that lasted for 166 days. Anti-correlations and positive correlations and their respective soft and hard X-ray lags are only detected in the first 100 days of the outburst when the luminosity is high. This suggests that the cross-correlations may be related to high luminosity. Positive correlations are detected in every state of XTE J1859+226, viz., hard state, hard-intermediate state (HIMS), soft-intermediate state (SIMS) and soft state. However, anti-correlations are only detected in HIMS and SIMS, anti-correlated hard lags are only detected in SIMS, while anti-correlated soft lags are detected in both HIMS and SIMS. Moreover, the ratio of the observations with anti-correlated soft lags to hard lags detected in XTE J1859+226 is significantly different from that in neutron star low-mass X-ray binaries (NS LMXBs). So far, anti-correlations are never detected in the soft state of BHXBs but detected in every branch or state of NS LMXBs. This may be due to the origin of soft seed photons in BHXBs is confined to the accretion disk and, for NS LMXBs, from both accretion disk and the surface of the NS. We notice that the timescale of anti-correlated time lags detected in XTE J1859+226 is similar with that of other BHXBs and NS LMXBs. We suggest that anti-correlated soft lag detected in BHXB may result from fluctuation in the accretion disk as well as NS LMXB., 16 pages, 11 figures

The Nihewan Formation, northern China is ideal for studying environmental changes during the early Pleistocene. In conjunction with palaeomagnetic measurements, pollen and grain-size analyses were conducted on 120 samples from a ~24 m long section (2.2-1.8 Ma) of core NHA from the Nihewan Basin, in order to reconstruct past vegetation and climatic changes. The pollen assemblages were dominated by Pinus, indicating that the vegetation was primarily pine forest and that the climate was relatively warm and wet. From 2.15-1.92 Ma, deciduous broad-leaved tree pollen significantly increased to >10% of the total, showing that more broad-leaved trees grew in the study area during the warmest and wettest period in the study section. From 1.92-1.78 Ma (coeval with the Olduvai event), Pinus and broad-leaved tree pollen types decreased. The percentages of Picea (>20%), Artemisia and Chenopodiaceae increased, indicating that spruce forests expanded, the openness of the forested areas increased and the climate became cold and dry. The vegetation changes reconstructed during the Olduvai period indicates that the climate in the Nihewan Basin was cold and dry, relating to global cooling facilitated by the uplift of the Tibetan Plateau and the strengthening of the winter monsoon.

Electrospun polymer nanofibrous mats loaded with ionic liquids (ILs) and lithium salts are promising non-volatile electrolytes owing to their high ionic conductivities. However, the large cations of ILs are difficult to diffuse into solid electrodes, whereas the lithium ions in ILs tend to form anionic complexes with the IL anions, reducing the number of free lithium ions. To address these issues, octa(3-hydroxy-3-methylbutyldimethylsiloxy) polyhedral oligomeric silsesquioxane (POSS-OH), which has large specific surface area and functionality number, is incorporated into electrospun poly(vinylidene fluoride-co-hexafluoropropylene) (PVDF-co-HFP) nanofibrous mats, and the mats are used to host LiClO4/1-butyl-3-methylimidazolium tetrafluoroborate (BMIM+BF4−). It is found that POSS-OH can significantly increase both ionic conductivity and lithium transference number of the electrolytes owing to the Lewis acid-base interactions of POSS-OH with ClO4− and BF4−. The electrochromic device using the hybrid mat (with 5 wt% POSS-OH) loaded with LiClO4/BMIM+BF4− as the electrolyte shows significantly improved transmittance contrast and switching time, as a result of increased number of free lithium ions.