ALUMINUMDODECATUNGSTOPHOSPHATE (Al0.9H0.3PW12O40) NANOTUBE AS A SOLID ACID CATALYST ONE-POT PRODUCTION OF BIODIESEL FROM WASTE COOKING OIL

Solid nanocatalyst aluminum dodecatungstophosphate (Al0.9H0.3PW12O40, abbreviated as AlPW) with nanotube structure was synthesized through a natural cellulose fiber template. The AlPW nanotubes, which are highly water-tolerant and acid-tolerant, can be described as green double acids, as they combine both Brønsted and Lewis acid sites. They have been applied as an efficient nanoheterogeneous catalyst for the preparation of biodiesel from waste cooking oil containing 26.89 wt% high free fatty acids (FFAs) and 1% moisture via esterification of FFAs and transesterification of triglycerides in one pot under mild conditions

Determination of fundamental properties of an M31 globular cluster from main-sequence photometry

M31 globular cluster B379 is the first extragalactic cluster, the age of which was determined by main-sequence photometry. In this method, the age of a cluster is obtained by fitting its CMD with stellar evolutionary models. However, different stellar evolutionary models use different parameters of stellar evolution, such as range of stellar masses, different opacities and equations of state, and different recipes, and so on. So, it is interesting to check whether different stellar evolutionary models can give consistent results for the same cluster. Brown et al. (2004a) constrained the age of B379 by comparing its CMD with isochrones of the 2006 VandenBerg models. Using SSP models of BC03 and its multi-photometry, Ma et al. (2007) independently determined the age of B379, which is in good agreement with the determination of Brown et al. (2004a). The BC03 models are calculated based on the Padova evolutionary tracks. It is necessary to check whether the age of B379 which, being determined based on the Padova evolutionary tracks, is in agreement with the determination of Brown et al. (2004a). So, in this paper, we re-determine its age using isochrones of the Padova stellar evolutionary models. In addition, the metal abundance, the distance modulus, and the reddening value for B379 are also determined in this paper. The results obtained in this paper are consistent with the previous determinations, which including the age obtained by Brown et al. (2004a). So, this paper confirms the consistence of the age scale of B379 between the Padova isochrones and the 2006 VandenBerg isochrones, i.e. the results' comparison between Brown et al. (2004a) and Ma et al. (2007) is meaningful. The results obtained in this paper are: the metallicity [M/H]=-0.325, the age $\tau=11.0\pm1.5$ Gyr, the reddening value E(B-V)=0.08, and the distance modulus $(m-M)_{0}=24.44\pm0.10$.Comment: Accepted for Publication in PASP, 7 pages, 1 figure and 1 tabl

Hypergeometric function expressions for the molecule-micropore Lennard--Jones potential

We present hypergeometric function expressions for the molecule-micropore Lennard--Jones potential in cylindrical pores, in which the cylindrical wall can be a surface, or have thickness or have infinite thickness. These expressions are useful in theoretical study and computer simulations of fluids in micropore of circular cross sections

Public Housing of Early Modern Tianjin (1928-1937)

Societal reform, the planning and construction of public housing and the introduction of new building typologies went hand in hand in early modern China. Western and Japanese debates on public housing served as models, and Chinese scholars and professionals with the support of the KMT (Kuomintang) developed public housing as a sign of innovation both in terms of societal organization and building typology. Using the under-researched case of Tianjin’s public housing in the so-called Golden Decade (1928 -1937) as a case study, the paper first explores how journals and foreign trained Chinese scholars introduced the concept of modern housing to China through publications, and early constructions. Notably the YMCA Labours Model New Village in Shanghai impressed the KMT leader Chiang Kai-shek. It then explores three public housing projects developed for Tianjin, only one of which was realized. Exploring the locations, architectural designs, renting regulations and management rules of these projects, the paper argues that these projects (both planned and realized) aimed mostly at poor families, and served as a means to solve housing problems and reform society as well as to police the poor. The public housing projects in this period formed the foundation for later public housing in China

Quasi-unit regularity and QB-rings

Some relations for quasiunit regular rings and QB-rings, as well as for pseudounit regular rings and QB ∞-rings, are obtained. In the first part of the paper, we prove that (an exchange ring R is a QB-ring) ⟺ (whenever x ∈ R is regular, there exists a quasiunit regular element w ∈ R such that x = xyx = xyw for some y ∈ R) ⟺ (whenever aR + bR = dR in R; there exists a quasiunit regular element w ∈ R such that a + bz = dw for some z ∈ R). Similarly, we also give necessary and sufficient conditions for QB ∞-rings in the second part of the paper.Отримано деякi спiввiдношення для квазiодиничних регулярних кiлець та QB-кiлець, а також для псевдоодиничних регулярних кiлець та QB∞-кiлець. У першiй частинi статтi доведено, що (кiльце R з властивiстю замiни є QB-кiльцем) ⇔ (якщо x∈R є регулярним, то iснує квазiодиничний регулярний елемент w∈R такий, що x=xyx=xyw для деякого y∈R) ⇔ (якщо aR+bR=dR in R в R, то iснує квазiодиничний регулярний елемент w∈R такий, що a+bz=dw для деякого z∈R). Аналогiчним чином отриманi необхiднi та достатнi умови для QB∞-кiлець наведено у другiй частинi статтi

CO₂ emissions and their spatial patterns of Xinjiang cities in China

City-level CO2 emission accounting is necessary to identify the different energy circumstances among all cities. However, due to a lack of data, energy consumption and emission statistics are not well documented. Focusing on the industrial production using fossil fuels, our work provides the first detailed city-level estimation of production-based sectoral CO2 emissions in the Xinjiang Uygur Autonomous Region. In 2010, 15 cities in Xinjiang emitted a total of 304.06 million tonnes CO2, and 97.7% of those emissions were related to fossil fuel combustion (i.e. energy-related emissions), with the remaining 2.3% from industrial processes associated with the production of cement (i.e. process-related emissions). The consumption of raw coal and crude oil were the main sources of Xinjiang's emissions (50.3% and 23.0%, respectively), whereas ‘petroleum processing and coking’ and ‘power and heat production’ were the two sectors that contributed the largest emissions at 32.6% and 27.9%, respectively. The cities in Xinjiang presented considerable variations in the total CO2 emissions and emissions per capita. The emissions intensity and emissions per capita shared similar distributions, and the emissions are significantly spatial autocorrelated. Cities whose economies relied on emission-intensive pillar industries and/or energy mainly sourced from raw coal tended to have high emissions per capita and high emissions intensities. Those cities included Altay, Changji, Hami and Shihezi. We also examined the time-series emissions of Urumqi, the largest city, from 2005 to 2015. Urumqi presented a generally rising trend in CO2 emissions over the decade, with emissions increasing by 324.2%. The major driving sector was ‘power and heat’, which showed increases in the total CO2 emissions and percentage of Xinjiang's emissions. Based on the findings, policy recommendations for emission reductions and low-carbon development for the cities in Xinjiang are provided, including adjusting the energy structure and introducing multiple industries