Preparation and characterization of new hybrid organic/inorganic systems derived from calcium (aminoalkyl)-phosphonates and -phosphonocarboxylates

We have studied the phenomenon of calcium complexation by lab synthesized amphiphilic (α-aminoalkyl)-phosphonocarboxylic or -phosphonic acids. The electrical conductivity of aqueous solutions of sodium salts of all these acids was measured versus the volume of a calcium salt solution added. It appeared that calcium complexes are formed in a Ca/P atomic ratio close to 1. Calcium phosphonocarboxylates and calcium phosphonates were also precipitated by mixing aqueous solutions of disodium salts of phosphorus amphiphiles and calcium nitrate solutions. Before chemical analysis, these complexes were calcined to remove the organic part. In the mineralized products, calcium and phosphate were assayed: the Ca/P atomic ratio was equal to 1. X-ray diffraction and IR spectroscopy showed that they are made entirely of β pyrophosphate (Ca2P2O7), a result in agreement with previous chemical analysis. The chemical formula of the starting calcium complexes could be written as CaL·2H2O (L= ligand). The SEM micrographs of these complexes show plate-like structures. XRD patterns are characteristic of layered structures. These facts suggest that calcium complexes are composed of alternating bimolecular layers of calcium alkylphosphonocarboxylates or calcium alkylphosphonates, the chains being tilted and partially interdigitated

Development Transporation River On The Past Banjar Society

The main problem examined in this research is the development of river transportation during the Banjarese era, the research results show that rivers are part of people's lives the city Banjarmasin, but currently the use of rivers as water transportation infrastructure appears be decreasing. Community activities in Banjarmasin City tend to shift to using land transportation. Apart from that, the lack of attention and participation by government, private sector and society in the field of river transportation has resulted river transportation being unable to compete with land transportation. As a city that has many rivers, almost all aspects of people's lives in Banjarmasin depend on rivers, both for daily activities and for economic activities. Not only that, there are even many community beliefs and traditions related to rivers. Therefore, it is not an exaggeration to say that river culture part of the life of the people of Banjarmasin. The existence of many rivers in the middle of city also encourages people to develop each area. And of is the : methode used this Is research uses historical methode throughted the Heuristic stage (data collection), internal and external criticism of the data obtained, interpretation and historiography of historical writing based on the data that has been obtained according to the researcher's objectives. The novelty of this research is that previous research did not specifically discuss the development of river transportation in the past in Banjarese society, most of which only revealed the history and phenomena, this made the researcher try to make this article specifi

RANCANG BANGUN MESIN PENCACAH BOTOL PLASTIK ( DESIGN COUNTING MACHINES PLASTIC BOTTLES )

Salah satu bentuk pencemaran lingkungan yang sering kita temui dan seringkali menimbulkan masalah adalah pencemaran yang disebabkan oleh sampah. Masalah ini semakin besar akibatnya seiring dengan makin banyaknya penggunaan barang-barang plastik pada era modern sekarang ini. Dengan dapat didaur ulang maka banyak potensi dari sampah botol plastik yang masih bisa dimanfaatkan. Untuk menunjang langkah tersebut maka dibuat suatu perancangan mesin yang sederhana untuk mengolah sampah. Mesin Pencacah Sampah Botol Plastik ini berfungsi untuk menghancurkan sampah plastik hingga berbentuk kepingan-kepingan kecil sehingga dapat memudahkan langkah-langkah dalam proses pendaur ulangan. Dengan panjang 900 mm, lebar 450 dan tinggi 800 mm, pencacah ini digerakkan oleh motor penggerak dengan putaran 1400 rpm dan daya 11,65 hp yang mana memiliki sistem kerja sebagai berikut, motor memutar pulley penggerak, kemudian ditransmisikan ke sistem menggunakan transmisi belt untuk memutar poros pisau iris yang berputar pada 974 rpm dan putaran dari poros ini ditransmisikan menggunakan transmisi gear untuk memutar poros roll press yang berputar pada 447 rpm. Motor juga dihubungkan langsung menggunakan poros dan gear untuk memutar poros pisau potong sehingga putarannya sama dengan motor listrik. Perhitungan dimulai dengan merencanakan transmisi yang meliputi perencanaan pulley, belt, poros dan bantalan. Setelah itu menghitung daya yang dibutuhkan untuk mengoperasikan pencacah ini. Hasil dari botol plastik yang dicacah belum sesuai dengan target rancangan. Dari hasil perhitungan diketahui bahwa kapasitas mesin yaitu 428,4 kg/jam untuk botol ukuran 1500 ml dan 284,4 kg/jam untuk botol ukuran 600 ml. Kata Kunci : Botol plastik, pencacah, roll press, puli, bantalan One form of environmental pollution that we often encounter and often cause problems is the pollution caused by garbage . This problem is getting bigger as a result in line with the increasing number of the use of plastic items in this modern era . With recyclable so much potential from waste plastic bottles that can still be used . To support these measures then created a simple machine design to process waste . This Machine serves to destroy the plastic waste in to small pieces so is ease the steps in the process of recycling. With a length of 900 mm, width 450 and height 800 mm, this enumerator is driven by the motor with 1400 rpm rotation and power 11.65 hp which has a working system as follows, rotate the motor drive pulley, and then transmitted to the transmission system using belt to rotate the iris blades rotating shaft at 974 rpm and the rotation of the shaft is transmitted using a transmission gear to rotate the press roll shaft rotating at 447 rpm. Motor also be connected directly using the shaft and gear to rotate the cutter so that the rotation axis is equal to the motor. The calculations begins with a transmission plan that includes planning pulley, belt, shaft and bearings. After that, calculate power needed to operate this trace. The results of plastic bottle enumeration is not according to the target design. The result of the calculation is known that the capacity of the machine that is 428.4 kg/h for 1500 ml bottle size and 284.4 kg/h for a 600 ml bottle size. Keywords : Plastic bottle , enumerators roll press , pulleys , bearing

Nutrient recovery and fractionation of anaerobic digester effluents employing pilot scale membrane technology

Anaerobic Digester (AD) waste, known as digestate (spent anaerobically digested effluents) of agricultural origin, was collected for a feasibility study on the use of membrane filtration to fractionate phosphate and ammonia from digestate into nutrient streams. The digestate was pre-treated to remove bulk solids and then filtered using diafiltration (DF) with ultrafiltration (UF) (5.65 psi TMP) and then nanofiltration (NF) (operating pressure 253.82 psi). Having set the pre-treated effluents at pH 4.0, retention of phosphate reached 6.78 mmols L−1 during UF with lower values being achieved with repeated DF steps. In contrast, nitrogen retention was lower at 8.21 mmols L-1 and was continuously dropping at each DF step. During NF phosphorus was shown to be strongly retained by the membrane at 31.8 mmols L−1, while retention of ammonium was low at 13.4 mmols L-1 demonstrating the potential for this combination of membrane types for fractionating high value components from AD waste

Comparison of Asian Aquaculture Products by Use of Statistically Supported Life Cycle Assessment

We investigated aquaculture production of Asian tiger shrimp, whiteleg shrimp, giant river prawn, tilapia, and pangasius catfish in Bangladesh, China, Thailand, and Vietnam by using life cycle assessments (LCAs), with the purpose of evaluating the comparative eco-efficiency of producing different aquatic food products. Our starting hypothesis was that different production systems are associated with significantly different environmental impacts, as the production of these aquatic species differs in intensity and management practices. In order to test this hypothesis, we estimated each system's global warming, eutrophication, and freshwater ecotoxicity impacts. The contribution to these impacts and the overall dispersions relative to results were propagated by Monte Carlo simulations and dependent sampling. Paired testing showed significant (p < 0.05) differences between the median impacts of most production systems in the intraspecies comparisons, even after a Bonferroni correction. For the full distributions instead of only the median, only for Asian tiger shrimp did more than 95% of the propagated Monte Carlo results favor certain farming systems. The major environmental hot-spots driving the differences in environmental performance among systems were fishmeal from mixed fisheries for global warming, pond runoff and sediment discards for eutrophication, and agricultural pesticides, metals, benzalkonium chloride, and other chlorine-releasing compounds for freshwater ecotoxicity. The Asian aquaculture industry should therefore strive toward farming systems relying upon pelleted species-specific feeds, where the fishmeal inclusion is limited and sourced sustainably. Also, excessive nutrients should be recycled in integrated organic agriculture together with efficient aeration solutions powered by renewable energy sources. © 2015 American Chemical Society.Additional coauthors: M. Mahfujul Haque Froukje Kruijssen, Geert R. de Snoo, Reinout Heijungs, Peter M. van Bodegom, and Jeroen B. Guiné

Improving the Antimicrobial Power of Low-Effective Antimicrobial Molecules Through Nanotechnology

[EN] The objective of this work was on the one hand to assess the antibacterial activity of amines anchored to the external surface of mesoporous silica particles against Listeria monocytogenes in comparison with the same dose of free amines as well. It was also our aim to elucidate the mechanism of action of the new antimicrobial device. The suitability of silica nanoparticles to anchor, concentrate and improve the antimicrobial power of polyamines against L. monocytogenes has been demonstrated in a saline solution and in a food matrix. Moreover, through microscope observations it has been possible to determine that the attractive binding forces between the positive amine corona on the surface of nanoparticles and the negatively charged bacteria membrane provoke a disruption of the cell membrane. The surface concentration of amines on the surface of the nanoparticles is so effective that immobilized-amines were 100 times more effective in killing L. monocytogenes bacteria than the same amount of free polyamines. This novel approach for the creation of antimicrobial nanodevices opens the possibility to put in value the antimicrobial power of natural molecules that have been discarded because of its low antimicrobial power. Practical ApplicationConsumers demand for high-quality products, free from chemical preservatives, with an extended shelf-life. In this study, a really powerful antimicrobial agent based on a nanomaterial functionalized with a non-antimicrobial organic molecule was developed as a proof of concept. Following this approach it could be possible to develop a new generation of natural and removable antimicrobials based on their anchoring to functional surfaces for food, agricultural or medical purposes.Authors gratefully acknowledge the financial support from the Ministerio de Economia y Competitividad and FEDER-EU (Projects AGL2015-70235-C2-1-R, AGL2015-70235-C2-2-R and MAT2015-64139-C4-1-R [MINECO/FEDER]). M.R.R. is grateful to the Ministerio de Educacion, Cultura y Deporte for her grant (AP2010-4369). The authors also thank the Electron Microscopy Service at the UPV for support.Ruiz Rico, M.; Pérez-Esteve, É.; De La Torre-Paredes, C.; Jiménez Belenguer, AI.; Quiles Chuliá, MD.; Marcos Martínez, MD.; Martínez-Máñez, R.... (2018). Improving the Antimicrobial Power of Low-Effective Antimicrobial Molecules Through Nanotechnology. Journal of Food Science. 83(8):2140-2147. https://doi.org/10.1111/1750-3841.14211S21402147838Al Shamsi, M., Al Samri, M. 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(2011). Effectiveness of High Intensity Light Pulses (HILP) treatments for the control of Escherichia coli and Listeria innocua in apple juice, orange juice and milk. Food Microbiology, 28(1), 14-20. doi:10.1016/j.fm.2010.07.023Park, S.-Y., Barton, M., & Pendleton, P. (2012). Controlled release of allyl isothiocyanate for bacteria growth management. Food Control, 23(2), 478-484. doi:10.1016/j.foodcont.2011.08.017Pérez-Esteve, É., Oliver, L., García, L., Nieuwland, M., de Jongh, H. H. J., Martínez-Máñez, R., & Barat, J. M. (2014). Incorporation of Mesoporous Silica Particles in Gelatine Gels: Effect of Particle Type and Surface Modification on Physical Properties. Langmuir, 30(23), 6970-6979. doi:10.1021/la501206fPérez-Esteve, É., Ruiz-Rico, M., de la Torre, C., Villaescusa, L. A., Sancenón, F., Marcos, M. D., … Barat, J. M. (2016). Encapsulation of folic acid in different silica porous supports: A comparative study. 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Structural features of Penicillin acylase adsorption on APTES functionalized SBA-15. Microporous and Mesoporous Materials, 116(1-3), 157-165. doi:10.1016/j.micromeso.2008.03.030Singh, S., Barick, K. C., & Bahadur, D. (2011). Surface engineered magnetic nanoparticles for removal of toxic metal ions and bacterial pathogens. Journal of Hazardous Materials, 192(3), 1539-1547. doi:10.1016/j.jhazmat.2011.06.074SLOWING, I., VIVEROESCOTO, J., WU, C., & LIN, V. (2008). Mesoporous silica nanoparticles as controlled release drug delivery and gene transfection carriers☆. Advanced Drug Delivery Reviews, 60(11), 1278-1288. doi:10.1016/j.addr.2008.03.012Tang, F., Li, L., & Chen, D. (2012). Mesoporous Silica Nanoparticles: Synthesis, Biocompatibility and Drug Delivery. Advanced Materials, 24(12), 1504-1534. doi:10.1002/adma.201104763Wehling, J., Volkmann, E., Grieb, T., Rosenauer, A., Maas, M., Treccani, L., & Rezwan, K. (2013). 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Shapes of rotating normal fluid 3He versus superfluid 4He droplets in molecular beams

Previous single-pulse extreme ultraviolet and X-ray coherent diffraction studies revealed that superfluid 4He droplets obtained in free jet expansion acquire sizable angular momentum, resulting in significant centrifugal distortion. Similar experiments with normal fluid 3He droplets may help elucidating the origin of the of the large degree of rotational excitation and highlight similarities and differences of dynamics in normal and superfluid droplets. Here, we present the first comparison of the shapes of isolated 3He and 4He droplets following expansion of the corresponding fluids in vacuum at temperatures as low as ~ 2 K. Large 3He and 4He droplets with average radii of ~160 nm and ~350 nm, respectively, were produced. We find that the majority of the 3He droplets in the beam correspond to rotating oblate spheroids with reduced average angular momentum ($\Lambda$) and reduced angular velocities ($\Omega$) similar to that of 4He droplets. Given the different physical nature of 3He and 4He, this similarity in $\Lambda$ and $\Omega$ may be surprising and suggest that similar mechanisms induce rotation regardless of the isotope. We hypothesized that the observed distribution of droplet sizes and angular momenta stem from processes in the dense region close to the nozzle. In this region, the significant velocity spread and collisions between the droplets induce excessive rotation followed by droplet fission. The process may repeat itself several times before the droplets enter the collision-fee high vacuum region further downstream.Comment: 29 pages, 6 figure

Una colección de entremeses inédita y desconocida (con la edición de La cabeza encantada)

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Vaccine candidates derived from a novel infectious cDNA clone of an American genotype dengue virus type 2

BACKGROUND: A dengue virus type 2 (DEN-2 Tonga/74) isolated from a 1974 epidemic was characterized by mild illness and belongs to the American genotype of DEN-2 viruses. To prepare a vaccine candidate, a previously described 30 nucleotide deletion (Δ30) in the 3' untranslated region of DEN-4 has been engineered into the DEN-2 isolate. METHODS: A full-length cDNA clone was generated from the DEN-2 virus and used to produce recombinant DEN-2 (rDEN-2) and rDEN2Δ30. Viruses were evaluated for replication in SCID mice transplanted with human hepatoma cells (SCID-HuH-7 mice), in mosquitoes, and in rhesus monkeys. Neutralizing antibody induction and protective efficacy were also assessed in rhesus monkeys. RESULTS: The rDEN2Δ30 virus was ten-fold reduced in replication in SCID-HuH-7 mice when compared to the parent virus. The rDEN-2 viruses were not infectious for Aedes mosquitoes, but both readily infected Toxorynchites mosquitoes. In rhesus monkeys, rDEN2Δ30 appeared to be slightly attenuated when compared to the parent virus as measured by duration and peak of viremia and neutralizing antibody induction. A derivative of rDEN2Δ30, designated rDEN2Δ30-4995, was generated by incorporation of a point mutation previously identified in the NS3 gene of DEN-4 and was found to be more attenuated than rDEN2Δ30 in SCID-HuH-7 mice. CONCLUSIONS: The rDEN2Δ30 and rDEN2Δ30-4995 viruses can be considered for evaluation in humans and for inclusion in a tetravalent dengue vaccine