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Deposition of cocatalyst is an efficient way for photocatalytic water splitting to improve solar energy conversion efficiency, and its deposition method has been known to make a great effect. In this work, we introduced a sulfurization-assisted deposition method to load earth-abundant cobalt cocatalyst for the purpose of promoting water oxidation performance of Sm2Ti2S2O5 oxysulfide that is characterized with wide visible light absorption. The cobalt deposition introduced here undergoes first formation of CoSx by sulfurization at high temperature and subsequent conversion into CoOx by calcinations in air. Compared to conventionally impregnated cobalt or IrO2 colloids, the sulfurization-assisted cobalt deposition well maintains structure of photocatalyst and inhibits the formation of defect sites leading to better separation of photogenerated carriers and water oxidation performance. The apparent quantum efficiency of the optimized sample reaches 5.0% at 420 nm. The sulfurization-assisted deposition actual...

Background Based on the prodrug principle, aspirin and eugenol, as starting precursors, were esterified to synthesize aspirin eugenol ester (AEE). The aim of the present study was to evaluate the antithrombotic effect of AEE in an animal disease model. In order to compare the therapeutic effects of AEE and its precursors, aspirin, eugenol and a combination of aspirin and eugenol were designed at the same molar quantities as the AEE medium dose in the control group. Methods After oral administration of AEE (dosed at 18, 36 and 72 mg/kg) for seven days, rats were treated with k-carrageenan to induce tail thrombosis. Following the same method, aspirin (20 mg/kg), eugenol (18 mg/kg) and 0.5 % CMC-Na (30 mg/kg) were administered as control drug. Different drug effects on platelet aggregation, hemorheology, TXB2/6-keto-PGF1α ratio and blood biochemistry were studied. Results AEE significantly inhibited ADP and AA-induced platelet aggregation in vivo. AEE also significantly reduced blood and plasma viscosity. Moreover, AEE down-regulated TXB2 and up-regulated 6-keto-PGF1α, normalizing the TXB2/6-keto-PGF1α ratio and blood biochemical profile. In comparison with aspirin and eugenol, AEE produced more positive therapeutic effects than its precursors under the same molar quantity. Conclusion It may be concluded that AEE was a good candidate for new antithrombotic and antiplatelet medicine. Additionally, this study may help to understand how AEE works on antithrombosis in different ways.

The cell wall is a dynamic structure that is important for the pathogenicity of Candida albicans. Mannan, which is located in the outermost layer of the cell wall, has been shown to contribute to the pathogenesis of C. albicans, however, the molecular mechanism by which this occurs remains unclear. Here we identified a novel α-1,6-mannosyltransferase encoded by MNN10 in C. albicans. We found that Mnn10 is required for cell wall α-1,6-mannose backbone biosynthesis and polysaccharides organization. Deletion of MNN10 resulted in significant attenuation of the pathogenesis of C. albicans in a murine systemic candidiasis model. Inhibition of α-1,6-mannose backbone extension did not, however, impact the invasive ability of C. albicans in vitro. Notably, mnn10 mutant restored the invasive capacity in athymic nude mice, which further supports the notion of an enhanced host antifungal defense related to this backbone change. Mnn10 mutant induced enhanced Th1 and Th17 cell mediated antifungal immunity, and resulted in enhanced recruitment of neutrophils and monocytes for pathogen clearance in vivo. We also demonstrated that MNN10 could unmask the surface β-(1,3)-glucan, a crucial pathogen-associated molecular pattern (PAMP) of C. albicans recognized by host Dectin-1. Our results demonstrate that mnn10 mutant could stimulate an enhanced Dectin-1 dependent immune response of macrophages in vitro, including the activation of nuclear factor-κB, mitogen-activated protein kinase pathways, and secretion of specific cytokines such as TNF-α, IL-6, IL-1β and IL-12p40. In summary, our study indicated that α-1,6-mannose backbone is critical for the pathogenesis of C. albicans via shielding β-glucan from recognition by host Dectin-1 mediated immune recognition. Moreover, our work suggests that inhibition of α-1,6-mannose extension by Mnn10 may represent a novel modality to reduce the pathogenicity of C. albicans., Author Summary Mannan plays a crucial role in cell wall structure and virulence of the opportunistic pathogen Candida albicans. Both the invasive ability of the pathogen and the host defense against the pathogen contribute to the outcome of invasive infection. In the present study, we identified a novel α-1,6-mannosyltransferase, which was responsible for cell wall α-1,6-mannose backbone extension in C. albicans. We determined that α-1,6-mannose backbone is necessary for the pathogenesis of C. albicans due to its ability to shield β-(1,3)-glucan from the host Dectin-1 recognition and Th1/Th7 response. Our study highlights a novel strategy to enhance the host immune response towards C. albicans.

When Alpha met Beta: a tuneable α-β surface phase junction on Ga(2)O(3) can significantly improve photocatalytic overall water splitting into H(2) and O(2) over individual α-Ga(2)O(3) or β-Ga(2)O(3) surface phases. This enhanced photocatalytic performance is mainly attributed to the efficient charge separation and transfer across the α-β phase junction.

article i nfo Acid rain, which is caused mainly by dissolution of sulfur dioxide (SO2) and nitrogen oxides (NOx )i n the at- mosphere, has been reported to have negative effects on ecosystems. However, few investigations have fo- cused on the impacts of acid rain on soil CO2 emission in forest. In this study, the effects of simulated acid rain (SAR) on soil respiration (Rs )a nd its heterotrophic component (Rh) in a secondary forest in subtropical China were investigated. Soil CO2 efflux was measured by using a Li-8100 infrared gas analyzer with at- tached chamber. Measurements were generally made once a week from 21 March 2010 to 16 May 2011 in order to investigate the seasonal variations of Rs and Rh under different SAR treatments. Soil temperature and moisture at the depth of 5 cm were measured at the time of soil CO2 efflux measurements. Results in- dicated that different SAR treatments exhibited similar seasonal patterns of Rs and Rh .S easonal meanRs rates for the CK (deionized water), A1 (pH 4.0), A2 (pH 3.0) and A3 (pH 2.0) treatments were 2.63, 1.92, 1.89 and 2.16 μmol m �2 s �1 , respectively, while mean Rh rates for the four treatments were 1.80, 1.64, 1.76 and 1.79 μmol m �2 s �1 , respectively. Two-factor analysis (respiration components and SAR) of vari- ance implied that SAR had signi ficant (p=0.031) effects on soil CO2 emissions, but this was contingent on the specific respiration components. SAR showed significant inhibition effects on Rs (autotrophic+ heterotrophic components) rather than Rh .T he ratio ofRh to Rs was significantly higher in the CK than in the acid rain treatments (A1, A2 and A3). Soil temperature and moisture were two controlling factors regulating the seasonal patterns of Rs and Rh for each of the SAR treatment. Soil temperature and moisture accounted for more than 80% of the seasonal variations observed in Rs and Rh. This work highlights that the effects of SAR are important to consider in assessing the annual soil CO2 emission, particularly under the scenario of increasing acid rain pollution.

RATIONALE Primary central nervous system lymphoma (PCNSL) is a rare form of non-Hodgkin lymphoma with a dismal outcome. Most patients relapse in intracranial sites and

Rationale:Primary central nervous system histiocytic sarcoma (PCNSHS) is a rare lymphohematopoietic tumor with a histiocytic cell origin. To our knowledge, only 28 cases have been published in English and 2 cases in Chinese.Patient concerns:A 49-year-old Asian female presented to the hospita

Rationale:Chondromyxoid fibroma (CMF) is a rare benign bone neoplasm which often occurs in the lower extremities. Little is known about the radiological and histological presentation of CMF in the sellar region.Patient concerns:A 16-year-old Asian male presented to the hospital 12 months ago

A four-year field experiment was performed from March 2010 to February 2014 in order to investigate the contribution of different respiratory components to soil respiration and the temperature sensitivity of different respiratory components. Four blocks were arranged in field, and there were trenched and un-trenched plots in each block. Trenching, which can exclude roots, was performed around the trenched plots. A portable soil CO2 fluxes system ( Li-8100) was used to measure soil respiration rates. Soil temperature and soil moisture were simultaneously observed when measuring soil respiration rates. The results showed that the heterotrophic respiration rate in the trenched plots and the soil respiration rate in the un-trenched plots had the same seasonal pattern. Soil respiration rate in the un-trenched plots was significantly (P0.001) higher than that in the trenched plots. Mean soil respiration rates in untrenched plots and mean heterotrophic respiration rate in trenched plots were (2.59 ± 0.48 ) and (1.74 ± 0.28) μmol x (M2 x s)(-1), respectively. There was no significant (P0.05) difference in the mean soil respiration rate or mean heterotrophic respiration rate between measurement years. The relationship between heterotrophic respiration and soil respiration could be fitted with a proportion function. Heterotrophic and autotrophic respiration contributed 65.9% and 34.1% to the soil respiration, respectively. The main contributor to soil respiration was heterotrophic respiration. The relationship between the ratio of heterotrophic respiration to soil respiration and measurement date could be fitted with a linear function. An exponential function could be used to fit the relationship between heterotrophic respiration and soil temperature, and between autotrophic respiration and soil temperature. The temperature sensitivity coefficient (Q10) for heterotrophic respiration was lower than that for autotrophic respiration.

Isolation of metabolites fromPlumula nelumbinisled to the discovery of eleven compounds, including six flavonoids and five phenolderivatives. Their structures have been determined on the basis of chemical and spectroscopic data. Most of them, such as compounds1,4,6,8, and10,have shown inhibitory activity against hospital-acquired methicillin-resistantStaphylococcus aureus(HA-MRSA). MICs of compound8against SA-200195 and SA-300150 were 2 μg/mL and 8 μg/mL, respectively. And the antioxidant activity of isolated compounds was determined by checking the scavenging activity against three different radicals: 2,2-diphenyl-1-picrydrazyl (DPPH) radical, hydroxyl radical (OH∙), and superoxide anion (O2∙-), as well as xanthine oxidase inhibition. All flavonoids showed strong antioxidant activity. And compound6displayed the highest inhibitory effect against xanthine oxidase with IC50value of 8.2 μg/mL.

Unprecedented organocatalyzed asymmetric cascade reactions have been developed for the facile synthesis of chiral spirooxindole-based isotetronic acids and 5-1h-pyrrol-2-ones. the asymmetric 1,2-addition reactions of alpha-ketoesters to isatins and imines by using an acid-base bifunctional 6'-oh cinchona alkaloid catalyst, followed by cyclization and enolization of the resulting adducts, gave chiral spiroisotetronic acids and 5-1h-pyrrol-2-ones, respectively, in excellent optical purities (up to 98% ee). ft-ir analysis supported the existence of hydrogen-bonding interaction between the 6'-oh group of the cinchona catalyst and an isatin carbonyl group, an interaction that might be crucial for catalyst activity and stereocontrol.

Rationale Primary thyroid-like low-grade nasopharyngeal papillary adenocarcinoma (TL-LGNPPA) is an extremely rare malignant nasopharyngeal tumor with features resembling papillary thyroid carcinoma including nuclear positive expression of thyroid transcription factor-1 (TTF-1). Patient concerns A 64-year-old male presented with nasal bleeding and a foreign body sensation of the nasopharynx. Laryngoscopy revealed a 2.0-cm broad-based mass with a smooth surface on the posterior wall of the nasopharynx. A biopsy was obtained. Diagnoses Histopathologic examination demonstrated tumor cells arranged in both papillary and glandular architecture. The tumor cells express nuclear immunoreactivity for TTF-1. The diagnosis of TL-LGNPPA was made. Interventions After the patient was diagnosed with TL-LGNPPA, he underwent complete surgical resection. Outcomes There was no recurrence or evidence of metastatic disease at the 12-month follow-up. Lessons TL-LGNPPA is easy to misdiagnose as metastatic papillary thyroid carcinoma or other relative primary adenocarcinomas. It is important to have a broad differential diagnosis and know the key features of each entity because the prognosis and clinical treatment of each may differ.

Cocatalysts have been extensively used to promote water oxidation efficiency in solar-to-chemical energy conversion, but the influence of interface compatibility between semiconductor and cocatalyst has been rarely addressed. Here we demonstrate a feasible strategy of interface wettability modification to enhance water oxidation efficiency of the state-of-the-art CoO(x)/Ta3N5 system. When the hydrophobic feature of a Ta3N5 semiconductor was modulated to a hydrophilic one by in situ or ex situ surface coating with a magnesia nanolayer (2-5 nm), the interfacial contact between the hydrophilic CoO(x) cocatalyst and the modified hydrophilic Ta3N5 semiconductor was greatly improved. Consequently, the visible-light-driven photocatalytic oxygen evolution rate of the resulting CoO(x)/MgO(in)-Ta3N5 photocatalyst is ca. 23 times that of the pristine Ta3N5 sample, with a new record (11.3%) of apparent quantum efficiency (AQE) under 500-600 nm illumination.

Introducing appropriate dual cocatalysts is one of the most efficient strategies to improve the photocatalytic activity. Herein, we investigated the promotion effect of dual cocatalysts on TiO2 for hydrogen production. Compared with the Pd/TiO2 and Ir/TiO2 with the individual cocatalyst, TiO2 coloaded with Pd and Ir species exhibited an obviously enhanced H2 production activity and reduced CO/H2 ratio. XPS and IR spectra of CO adsorption analysis indicated that the dual cocatalysts on TiO2 were actually composed of Pd(0) and partially oxidized IrOx, which acted as the reduction and oxidation cocatalysts, respectively. Interestingly, EDX elemental mappings of Pd and Ir indicated that the two elements on TiO2 were inclined to depositing together. The synergetic effect of reduction and oxidation cocatalysts with their intimate contact is proposed to contribute to the high H2 production activity, which is different from the common view that the reduction and oxidation sites should be spatially separated to avoid the charge recombination.

We present and analyze a novel optical heterodyne interferometer which enables significant nonlinearity compensation and increases system measurement resolution by twofold without requiring the doubling of optical pathlength. In this system, rather than measuring one pair of measurement and reference signals as in a conventional interferometer, we used two photodetectors to measure two measurement signals. Our theoretical analysis shows that the system nonlinearity caused by the nonorthogonality and the ellipticity of two-frequency input lights can be easily compensated through a single phase compensator in the new interferometer by more than a factor of 30.

The effects of nonlinearity on sub-500 fs pulse transmission over dispersion compensated fiber links using dispersion compensating fiber technique are investigated numerically and experimentally. The pulse broadening and recompression ratio of the 2.5-km transmission link is over 300. The postcompensated and precompensated links are compared when the input pulse energy ranges from 15 to 159 pJ. At high powers, self-phase modulation (SPM) degrades the pulse recompression process and provides an upper bound on the transmitted pulse energy. The SPM effect is stronger in the postcompensated link than in the precompensated link. A dramatic spectral narrowing effect was observed in the postcompensated link. Pulse energies up to tens of pJ, consistent with high quality communication, should be possible for a sub-500 fs pulse in such dispersion compensated links.

Zn-doped and Pb-doped β-Ga2O3-based photocatalysts were prepared by an impregnation method. The photocatalyst based on the Zn-doped β-Ga2O3 shows a greatly enhanced activity in water splitting while the Pb-doped β-Ga2O3 one shows a dramatic decrease in activity. The effects of Zn(2+) and Pb(2+) dopants on the activity of Ga2O3-based photocatalysts for water splitting were investigated by HRTEM, XPS and time-resolved IR spectroscopy. A ZnGa2O4-β-Ga2O3 heterojunction is formed in the surface region of the Zn-doped β-Ga2O3 and a slower decay of photogenerated electrons is observed. The ZnGa2O4-β-Ga2O3 heterojunction exhibits type-II band alignment and facilitates charge separation, thus leading to an enhanced photocatalytic activity for water splitting. Unlike Zn(2+) ions, Pb(2+) ions are coordinated by oxygen atoms to form polyhedra as dopants, resulting in distorted surface structure and fast decay of photogenerated electrons of β-Ga2O3. These results suggest that the Pb dopants act as charge recombination centers expediting the recombination of photogenerated electrons and holes, thus decreasing the photocatalytic activity.

This study was aimed to investigate the effects of simulated warming on soil respiration in a cropland under winter wheat-soybean rotation. Randomized experiments were carried out in the cropland. 6 Plots were arranged and there were 2 treatments, simulated warming and control. A portable soil CO2 fluxes system (LI-8100) was used to measure soil respiration rates. Soil CO2 production rates were determined by using a Barometric Process Separation (BaPS) method. Soil temperature and soil moisture were simultaneously determined when measuring soil respiration rates. Results indicated that soil respiration rates in different treatments showed similar seasonal variability, in accordance with the variability in soil temperature. Seasonal mean soil respiration rates for simulated warming and control treatments were 3.54 and 2.49 micromol x (m2 x s)(-1), respectively, during the winter wheat growth season, while they were 4.80 and 4.14 micromol x (m2 x s)(-1), respectively, during the soybean growth season. Simulated warming significantly (P0.05) enhanced soil respiration during both the winter wheat and soybean growth seasons. The impact of simulated warming on soil respiration was particularly obvious during the later growth stages of winter wheat (from heading to maturity stages) and soybean (from flowing to maturity stages). Further investigations suggested that, for both the winter wheat and soybean growth seasons, the relationship between soil respiration and soil temperature could be well explained (P0.01) by exponential functions. The temperature sensitivity (Q10) of soil respiration in the simulated warming treatments was significantly higher than that in the control treatments. The Q10 values for the simulated warming and control treatments were 1.83 and 1.26, respectively, during the winter wheat growth season, while they were 2.85 and 1.70, respectively, during the soybean growth season. This study showed that simulated warming significantly increased soil respiration in the cropland.

We study the influences of transmitter characteristics on polarization mode dispersion (PMD) impairments in optical transmission systems with both experiments and simulations. We show that transmitter imperfection, such as timing and amplitude jitters and pulse shape distortion, can significantly increase PMD impairments, especially when the differential group delay in the systems is large. Our simulation further shows that the increased PMD impairments due to transmitter imperfection will considerably reduce the effectiveness of using large system optical signal-to-noise ratio margin to combat PMD.

Soil respiration is an important process in carbon cycling. Understanding the processes and controlling factors of soil respiration are crucial in investigating the terrestrial carbon cycling. This article reviews the investigations about the factors controlling the temporal and spatial variability of soil respiration. The temporal and spatial variability in soil respiration is linked with climate, vegetation and soil factors. Air temperature and precipitation generally contribute great to the variability of soil respiration. Leaf area index (LAI), litter fall and fine root biomass are three plant-related factors that can be employed to explained the variability of soil respiration, while soil carbon content and texture are two soil factors responsible for the variability of soil respiration. Generally, climate, vegetation and soil factors contribute collectively to the temporal and spatial variability of terrestrial soil respiration. Temperature and precipitation, on the one hand, directly affect the root and microbial respiration rates. On the other hand, temperature and precipitation indirectly affect soil respiration by influencing the plant and microbial growth and soil conditions. In order to understand the controlling factors of the temporal and spatial variability of soil respiration, there are four main issues need to be addressed. The issues include quantitatively partitioning the autotrophic and heterotrophic components of soil respiration, standardizing the method and scale of measuring soil respiration, coupling measurements of soil respiration with environmental factors and performing more measurements of soil respiration in wetland ecosystems.

Trenched plots were set up in 2010 in a secondary forest in subtropical China, in order to investigate the seasonal variations of soil respiration (R(s)) and heterotrophic respiration (R(h)). Autotrophic respiration (R(a)) was estimated to be the difference between R(s) and R(h). Soil temperature and moisture were simultaneously measured during respiration measurements. Results indicated that R(s) and R(h) showed the similar seasonal variations. Seasonal mean rates for R(s), R(h) and R(a) were 3.42, 2.36 and 1.06 micromol x (m2 x s)(-1), respectively. Regression analysis indicated that R(h) increased with the increase of R(s); an natural logistic equation could be employed to explained the relationship between R(h) (y) and R(s) (x). Approximately 90.5% (R2 = 0.905) variations in R(h) could be explained by the equation. Apparent exponential relationships of R(h) and R(a) with soil temperature existed, but differed from each other and from the relationship for R(s). The exponential equations explained about 78.4%, 76.4% and 65.6% variations in R(s), R(h) and R(a), respectively, with the P values less than 0.01. The Q10 values for R(s), R(h) and R(a) were 1.97, 1.76 and 3.31, respectively. It was indicated that, seasonally, R(h) and R(a) represented 69% and 31% of R(s). R(a) showed significantly higher temperature sensitivity than R(h).

Field experiments were carried out in a winter wheat farmland, in order to investigate the effects of elevated ozone concentration on soil respiration, nitrification and denitrification. Three ozone concentration treatments, which were CK, T1 (100 nL x L(-1)) and T2 (150 nL x L(-1)), were arranged using open top chambers (OTCs). A portable soil CO2 fluxes system was used to measure soil respiration rates. Nitrification and denitrification rates were determined by using a Barometric Process Separation (BaPS) method. Results indicated that there were no significant differences (p0.05) in soil respiration rates among CK, T1 and T2 treatments. Mean soil respiration rates for CK, T1 and T2 treatments were (5.36 +/- 0.72), (5.08 +/- 0.04), (4.94 +/- 0.18) micromol x (m2 x s)(-1), respectively. No significant differences (p0.05) in mean soil nitrification and denitrification rates were observed between the treatments of CK and T2. During the experimental period, soil respiration showed an exponential relationship with soil temperature for each of the treatment. The Q10 (the respiratory flux at one temperature over the flux at a temperature 10 degrees C lower) values were 1.72, 1.58 and 1.51 for CK, T1 and T2 treatments, respectively. A correlation (Pearson product-momentum correlation) analysis showed that soil water content was correlated significantly (p0.05) with soil nitrification (r = 0.828) and denitrification (r = 0.890) rates for CK treatment. Soil water content was correlated significantly (p0.05) with soil nitrification rate for T2 treatment, with the correlation coefficient of 0.772. This study indicated that elevated ozone concentration did not significantly affect soil respiration, nitrification and denitrification rates in the winter wheat farmland. Elevated ozone concentration, however, significantly reduced the temperature sensitivity of soil respiration.

Anatase and rutile TiO(2) were investigated with photoluminescence techniques under the weak excitation condition, where trap states play a vital role in carrier dynamics. The visible emission of anatase and near-infrared (NIR) emission of rutile both exhibit extremely long lifetimes up to milliseconds. The decay processes can be well described by the power-law decay which corresponds to the trapping-detrapping effect. These results indicate that the luminescence processes in both anatase and rutile TiO(2) have a close relationship with trap states. The visible emission band was assigned to the donor-acceptor recombination. Oxygen vacancies and hydroxyl groups mainly serve as the donor and acceptor sites, respectively. The NIR luminescence is originated from the recombination of trapped electrons with free holes, while the trapped electrons were formed through two paths, direct trapping or trap-to-trap hopping. The trap states in anatase and rutile TiO(2) may largely influence the photocatalysis process of TiO(2) and determine the photocatalytic activity under stationary illumination.

Introducing appropriate dual cocatalysts is one of the most efficient strategies to improve the photocatalytic activity. Herein, we investigated the promotion effect of dual cocatalysts on TiO2 for hydrogen production. Compared with the Pd/TiO2 and Ir/TiO2 with the individual cocatalyst, TiO2 coloaded with Pd and Ir species exhibited an obviously enhanced H2 production activity and reduced CO/H2 ratio. XPS and IR spectra of CO adsorption analysis indicated that the dual cocatalysts on TiO2 were actually composed of Pd0 and partially oxidized IrOx, which acted as the reduction and oxidation cocatalysts, respectively. Interestingly, EDX elemental mappings of Pd and Ir indicated that the two elements on TiO2 were inclined to depositing together. The synergetic effect of reduction and oxidation cocatalysts with their intimate contact is proposed to contribute to the high H2 production activity, which is different from the common view that the reduction and oxidation sites should be spatially separated to avoid the charge recombination.

A composite Sr2TiO4/SrTiO3(La,Cr) heterojunction photocatalyst has been prepared by a simple in situ polymerized complex method. Upon Pt cocatalyst loading, this catalyst shows higher photocatalytic activity towards hydrogen production than individual SrTiO3(La,Cr) and Sr2TiO4(La,Cr) in the presence of methanol sacrificial reagent. Microscopic morphology studies show that well defined heterojunctions are formed by matching the lattice fringes of SrTiO3(La,Cr) and Sr2TiO4(La,Cr), and Pt was preferentially loaded on the surface of the Sr2TiO4(La,Cr) component in the composite Sr2TiO4/SrTiO3(La,Cr) photocatalyst. XPS and EPR analyses show that the composite photocatalyst also has the lowest amount of Cr6+ electron trapping sites. Band structure analysis by combining absorption spectroscopy and Mott–Schottky plots shows that, in the composite photocatalyst, the photogenerated electrons and holes tend to migrate from SrTiO3(La,Cr) to Sr2TiO4(La,Cr) and from Sr2TiO4(La,Cr) to SrTiO3(La,Cr), respectively. This kind of band structure can facilitate charge transfer and separation driven by the minor potential difference between the two components, which is further confirmed by the observation of long lived electrons in the time resolved FT-IR spectroscopic study. It is concluded that the superior photocatalytic activity of the composite heterojunction photocatalyst is due to efficient charge transfer and separation by well defined heterojunctions formed between SrTiO3(La,Cr) and Sr2TiO4(La,Cr), preferential loading of Pt nanoparticles on the Sr2TiO4(La,Cr) component, and the lowest amount of Cr6+ in the composite photocatalyst. The tailored design and synthesis of the composite heterojunction structure is a promising approach for the improvement of the photocatalytic activity of a photocatalyst.

The present invention relates in general to SPR sensors in which the sensing element is a planar lightpipe. More specifically, a planar lightpipe sensor configuration for measurement of SPR at a single angle operation is provided. The lightpipe of this sensor is beveled to facilitate coupling of substantially collimated white light, preferably TM polarized white light, at a selected single angle that excites SPR at the sensing area. Angle of incidence on the SPR sensing area is determined by bevel angle used. This embodiment is a zero order sensor in the sense that it allows measurement for a given analyte at only a single angle of incidence. In this embodiment, however, the lightpipe can have a plurality of SPR sensing area across its width to provide for multichannel sensing. Refractive index sensitivity of this configuration is estimated as 4×10-5 RI units.

A novel optical method for high-resolution angle measure- ment based on surface plasmon resonance (SPR) is presented. The phase difference between p and s polarization states when SPR takes place is very sensitive to the angle of incidence. Heterodyne interferom- etry is employed to measure this phase difference and thus to measure small angles. The feasibility of this method is demonstrated. The mea- surement resolution of 2310 25 deg can be achieved by this method.