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High-resolution X-ray powder diffraction using synchrotron radiation has been used to determine the unit-cell parameters of some of the n-alkanes within the range C, , H2, -C, , H, 22.These have, in general, been found to conform to the structural patterns predicted by Nyburg and Potworowski (Acta Crystallogr., Sect. B, 1973, 29, 347). Polymorphic behaviour has been observed for the n =even alkanes associated with increasing symmetry from a triclinic structure (space group Pl), to a monoclinic structure (space group P2,/a) and to an orthorhombic structure (mostly space group Pca2,) as the chain length increases. The n-alkanes C38H78, C4,,Hs2 and C44H90 were found to crystallize in the polytypic orthorhombic polymorph (space group Pbca) proposed by Boistelle et a/.

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hydrogen evolution reaction (HER). However, the most active catalysts based on platinum had impeded the practical applications due to the high cost and the scarcity of platinum. [2,3] On the other hand, many studies have proven various metal sulfides and metal phosphides as efficient, low-cost substitutes for the rare earth metals. [4][5][6][7][8][9] With porous and hierarchal structure, metal-organic frameworks (MOFs) were largely applied to fabricate metal hydroxide, metal sulfide, and metal phosphide. [10][11][12][13][14][15] By using nickel and cobalt incorporated Prussian blue analogue (PBA), Yu had demonstrated how to obtain a hollow Ni-Co-MoS 2 cube that could reach a current density of 10 mA cm −2 with an overpotential of 155 mV in acid. [16] Likewise, Song had fabricated copper-doped cobalt phosphide originated from ZIF-67, which could reach a current density of 10 mA cm −2 with an applied overpotential of 160 mV. [12] Another study exhibited by Paik's group had revealed the Ni-Co PBA phosphide could reach a current density of 10 mA cm −2 with an overpotential of 150 mV. [17] Nonetheless, the good performance of these catalysts based on MOFs were not comparable with catalysts that grew on different substrates with organized structure. Generally, the catalysts growing on a substrate could reach a higher current density with a lower charge resistance and a larger active area. [18][19][20] As Sun's group had demonstrated, the Fe-doped CoP nanoarray on titanium foil could reach a current density of 10 mA cm −2 with an overpotential of 78 mV. When the applied overpotential was 230 mV, the current density was remarkable, with a value of 240 mA cm −2 . [21] To this end, we believe the HER performance of catalysts derived from MOFs could be largely improved if regular MOFs arrays were produced as precursor.Recently, Kitagawa has reported the synthesis of porous coordination polymers from a sacrificial metal oxide precursor, which was named as a pseudomorphic replication method. [22] During this pseudomorphic replication procedure, a secondary crystal structure was built while the primary morphology was conserved. Inspired by this method, Rabu has used layerstructured Cu 2 (OH) 3 (OAc)·H 2 O as both a metal reservoir and For the first time, a 3D Prussian blue analogue (PBA) with well-defined spatial organization is fabricated by using a nickel hydroxide array as a precursor. The nickel hydroxide arrays are synthesized in titanium foil and reacted with K 3 [Fe(CN) 6 ]. The plate-like morphology of the nickel hydroxide is perfectly preserved and combined with abundant PBA nanocubes. After phosphidation at 350 °C, the obtained sample demonstrated excellent hydrogen evolution reaction (HER) activity in both acid and alkaline solutions to reach a current density of 10 mA cm −2 with an overpotential of only 70 and 121 mV, respectively. With an overpotential of 266 mV, it can reach a larger current density of 500 mA cm −2 in acid. The efficient HER activity of the obtained sample is mainly ascribed to its structural adv...

Simultaneous, 6-week feeding trials were conducted in which diets containing menhaden, corn, coconut and hydrogenated menhaden oil at 7.0%, plus a diet containing 14% menhaden oil, were fed to triplicate groups of juvenile red drum (Sciaenops ocellatus) at two different salinities (5 and 32%.). Weight gain was significantly (p < 0.05) affected by diet and salinity. Fish fed the diet containing 14% menhaden oil had the greatest weight gain; whereas, fish fed the diet containing coconut oil gained the least weight. Fish in brackish water had significantly greater weight gain than fish in full-strength seawater over the 6-week period, although fish fed coconut and saturated menhaden oil in brackish water had reduced survival. Dietary lipid also significantly affected muscle and liver total lipid, hepatosomatic index (HSI), and intraperitoneal fat (IPF) ratio, as fish fed the diets containing 14% menhaden oil had higher values for all of these body condition indices.After the feeding trial, fish were subjected to a chronic cold tolerance assay. In the chronic trial, where temperature was gradually reduced over a 3-week period, fish fed the diets containing menhaden oil had significantly lower median lethal temperatures (MLT) than those fish fed the diets containing coconut, corn and saturated menhaden oils. No significant effects of cold exposure were observed on muscle and liver total lipid. Cold exposure prompted a modification in lipid metabolism by lowering total saturated fatty acids and raising (n - 3) highly unsaturated fatty acids (HUFA) in the neutral lipid of liver. Fish with the lowest MLT in the chronic assay exhibited signs of conserving (n - 3) HUFA and depleting (n - 6) fatty acids [primarily 18:2 (n - 6)], resulting in higher (n - 3)/(n - 6) ratios in the polar lipid of liver. These data suggest that the lower lethal temperature of juvenile red drum can be reduced through dietary manipulation involving the inclusion of high levels of dietary lipid rich in (n - 3) HUFA.

A six-week feeding trial was conducted to evaluate the use of a yeast-based, certified organic protein source as a replacement for fish meal in diets for cobia. Five experimental diets were formulated to provide 40% crude protein and 11% dietary lipid (dry matter basis) with the yeast-based protein source replacing Special Select® menhaden fish meal at 25%, 50%, 75% and 100% of dietary protein. Ten juvenile cobia (initial weight 11.5 g/fish) were randomly stocked in triplicate 300 l circular fiberglass tanks (n = 30 treatment − 1 ) and hand-fed the diets based upon total tank biomass two times daily at 0900 and 1400 h. Fish were group weighed weekly to monitor performance and adjust feeding rations. Water temperature and salinity were maintained at 27°C and 15‰, respectively. At the end of the feeding trial, weight gain, ranging from 86% to 512%, and feed conversion ratio values, ranging from 1.9 to 5.8, were significantly affected by the inclusion of the yeast-based protein source, with decreasing values as inclusion levels of the yeast-based protein source rose above 25% of dietary protein. Cobia fed the diet containing 25% of dietary protein from the yeastbased protein source had equal weight gain and feed conversion ratio values as fish fed the control diet composed of 100% fish meal (503 vs. 512 and 1.9 vs. 1.9, respectively). Biological indices including hepatosomatic index, visceral somatic index and muscle ratio were all similarly affected by inclusion of the yeast-based protein source, with significant impacts when inclusion levels rose above 25% of dietary protein. As with the weight gain and feed efficiency ratio values, fish fed the diet containing 25% of protein from the yeast-based source had similar values as those observed in the control animals.This study represents the first attempt to utilize an organically certified protein source as a replacement for fish meal in diets for juvenile cobia. Although levels of inclusion of the yeast-based protein source above 50% of dietary protein resulted in detrimental effects on production characteristics, the data clearly suggest that, at a minimum, 25% of dietary protein can be provided by this yeast-based protein in diets for cobia.

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