THE SYNTHESIS OF ACETALS AND KETALS OF THE REDUCED SUGAR MANNOSE AS FUEL SYSTEM ICING INHIBITORS.

ABSTRACT

The current fuel system icing inhibitor additives used in both the military and commercial airlines are ethylene glycol monomethyl ether (EGME) and diethylene glycol monomethyl ether (DiEGME)These deicing compounds are toxic at the concentrations that are required for effective deicing. When fuel system sumps, filters and storage tanks are drained, they contain EGME/DiEGME and create a personnel hazard. Acetals and ketals of reduced sugars represent viable alternatives to glycol based additives. They are inexpensive, fuel stable for at least one year and show similar icing inhibitor characteristics. This paper summarizes the synthesis and fuel studies for these compounds.     

Versatile 3′ Functionalization of CRISPR Single Guide RNA

Specific applications of CRISPR/Cas genome editing systems benefit from chemical modifications of the sgRNA. Herein we describe a versatile and efficient strategy for functionalization of the 3′-end of a sgRNA. An exemplary collection of six chemically modified sgRNAs was prepared containing crosslinkers, a fluorophore and biotin. Modification of the sgRNA 3′-end was broadly tolerated by Streptococcus pyogenes Cas9 in an in vitro DNA cleavage assay. The 3′-biotinylated sgRNA was used as an affinity reagent to identify IGF2BP1, YB1 and hnRNP K as sgRNA-binding proteins present in HEK293T cells. Overall, the modification strategy presented here has the potential to expand on current applications of CRISPR/Cas systems.     

FUEL SYSTEM ICING INHIBITORS: THE SYNTHESIS OF ESTERS OF OXAACIDS

ABSTRACT

Currently ethylene glycol mono methyl ether (EGME) and diethylene glycol mono methyl ether (DiEGME) are used as fuel system icing inhibitor additives in both military and commercial aircraft. These compounds are toxic at the concentrations that required for effective deicing When fuel systems sumps, filters and storage tanks are drained, they contain EGME/DiEGME and create hazards for personnel. Ethyl esters synthesized from oxaacids have been identified as possible fuel system icing inhibitor additive replacements. These compounds were synthesized from oxaacids and ethanol by an acid catalyzed Fischer esterfication method The products were identified by infrared spectrometry, nuclear magnetic resonance spectrometry, and elemental analysis Physical characterization included boiling point determination and refractive index. The tested oxaesters were found to be fuel stable for at least two years by accelerated storage tests. Octanol-water partition coefficients were determined and indicate the compounds have a higher solubility in fuel than in water. These oxaesters are predicted to be non-toxic.     

中美工程机械租赁市场对比分析

目前，中国工程机械租赁企业可以按照国营、私营分类，也可以分为专业租赁企业和施工企业开展对外租赁业务两种。但是，因为行业中仍以小型个体企业为主，所以行业大小很难准确描述。但是，行业总量无疑是很大的。     

The effect of transport-blocking drugs on secretion of fluid and electrolytes by the mandibular gland of red kangaroos, Macropus rufus

Mechanisms of primary fluid formation by macropodine mandibular glands were investigated in anaesthetized red kangaroos using ion-transport and carbonic anhydrase inhibitors. Bumetanide at carotid plasma concentrations of 0.005-0.1 mmol/l progressively reduced a stable, acetylcholine-evoked flow rate of 1.02 +/- 0.024 ml/min to 0.16 +/- 0.016 ml/min (mean +/- SEM). Concurrently, saliva [Na], [Cl] and osmolality decreased, [K] and [HCO3] increased and HCO3 excretion was unaffected. High-rate cholinergic stimulation was unable to increase salivary flow above 12 +/- 1.5% of that for equivalent pre-bumetanide stimulation. Furosemide (1.0 mmol/l) and ethacrynate (0.5 mmol/l) caused depression of salivary flow and qualitatively similar effects on ion concentrations to those of bumetanide. Amiloride (up to 0.5 mmol/l) caused no reduction in salivary flow rates or [Na] but decreased [K] and [Cl] and increased [HCO3]. When compared with bumetanide alone, amiloride combined with bumetanide further augmented [K] and [HCO3] and lowered [Cl], but had no additional effects on Na or flow. At the higher level, 4-acetamido-4'- isothiocyanatostilbene-2,2'disulphonic acid (SITS) (0.05 and 0.5 mmol/l) stimulated fluid output, increased [HCO3] and [protein], and depressed [Na], [K] and [Cl]. Relative to bumetanide alone, SITS given with bumetanide had no additional effects on salivary flow or electrolytes. Methazolamide (0.5 mmol/l) in combination with bumetanide curtailed the decrease in [Cl] and the increases in [K] and [HCO3] associated with bumetanide. The residual methazolamide-resistant HCO3 excretion was sufficient to support 2-6% of primary fluid secretion. It was concluded that secretion of primary fluid by the kangaroo mandibular gland is initiated mainly (> 90%) by Cl transport resulting from Na-K-2Cl symport activity. A small proportion of the fluid secretion (up to 6%) appears to be supported by HCO3 secretion. No evidence was found for fluid secretion being dependent on Cl transport involving Na/H and Cl/HCO3 antiports or on HCO3 synthesis involving carbonic anhydrase.     

Soybean Biodiesel: Instability Reactions

It has been suggested that renewable energy sources be considered as replacements for middle distillate ground transportation and marine fuels. It is vital for the operational considerations of these fuels to investigate the many positives and negatives of incorporating these renewable energy sources in such systems. In proposing such a replacement, considerations must be given to the many problems that could arise including fuel storage stability, fuel solubility, oxidative stability, and seawater stability. Contrary to air environments, water environments have a pH factor that has to be considered. United States Navy shipboard fuel tanks compensate for diminishing fuel by the addition of seawater to the fuel tank. It was found that this would lead to fuel instability problems such as filter stoppage and other serious engine damage. Studies were performed to determine what in the soybean-derived biodiesels led to the observed fuel degradation.     

Real-time observations of Southern Ocean wave fields from theShuttle Imaging Radar

During the April and October 1994 flights of the space shuttle Endeavour, C-band synthetic-aperture radar (SAR) signal was acquired and processed in real-time into ocean wave images and two-dimensional image spectra by an on-board processor. The image spectra were transmitted to the ground as they were acquired. During 20 days of observations, spanning the two missions, over 100000 spectra were collected. These data provide the first truly synoptic directional measurements of the Southern Ocean wave field. With additional processing, estimates of ocean wavelength and propagation direction were extracted from the spectra. During the October mission, daily comparisons of these estimates with wave model predictions were made available at a World Wide Web site. The authors describe the computations performed by the processor and the real-time data flow and ground processing. In addition, they summarize and interpret some gross characteristics of the processor-observed real-time wave field from the April and October missions     

Excitotoxin lesions in primates as a model for Huntington's disease: histopathologic and neurochemical characterization

Excitotoxin lesions induced by quinolinic acid (QA) were made unilaterally in the caudate nucleus and putamen of 12 rhesus monkeys. Both acute (2-3 weeks) and chronic (4-6 months) effects were evaluated. Excitotoxin striatal lesions were characterized by a central zone of intense astrogliosis and marked neuronal depletion, which was surrounded by a transition zone in which there was partial neuronal sparing throughout the entire lesioned side. Immunocytochemical and enzyme histochemical markers for both large and medium-sized aspiny- and spiny-striatal neurons clearly demonstrated a selective pattern of neuronal vulnerability to the excitotoxic effects of QA within lesioned striata. Medium-sized spiny neurons containing calbindin Dk28, enkephalin, and substance P were disproportionately lost, while aspiny neuronal subpopulations containing NADPH diaphorase (NADPH-d) and choline acetyltransferase activity (ChAT) were relatively spared. Combined labeling by NADPH-d enzyme histochemistry and Nissl staining, as well as NADPH-d histochemistry and calbindin Dk28 immunocytochemistry, demonstrated significant increases in the ratio of aspiny to spiny neurons within the lesioned striata. Neurochemical measurements confirmed a loss of GABA and substance P-like immunoreactivity yet no significant depletion of somatostatin-like immunoreactivity, neuropeptide Y-like immunoreactivity, or ChAT were seen. The striatal patch-matrix pattern persisted, as demonstrated by acetylcholinesterase activity. The pattern was altered, however, in the chronic animals, such that the matrix zone was significantly reduced, while the total area of patches remained within normal limits. Ultrastructural analysis confirmed axon sparing lesions with neuronal loss and astrogliosis. Pretreatment of 3 monkeys with MK-801, a noncompetitive N-methyl-D-aspartate (NMDA) antagonist, blocked striatal QA neurotoxicity. The present results provide an experimental primate model which closely resembles the neuropathologic and neurochemical features of Huntington's disease. These findings further strengthen the possibility that an NMDA receptor-mediated excitotoxic process plays a role in the pathogenesis of this disorder.     

Multilayer microstrip structure analysis with matched loadsimulation

This paper presents a generalized approach to the full-wave analysis of multilayer microstrip structures. One of the structures studied is a new kind of microstrip bandpass filter realized in a double-layer dielectric substrate configuration. This filter demonstrates the use of the third (vertical) dimension in the design of microstrip devices. The approach involves the mixed potential integral equation technique, the Method of Moments, and an S-parameter extraction technique based on a simple form of Matched Load Simulation. Simulated and measured results for various microstrip structures are presented and show good agreement. The approach is demonstrated in detail for 2-port structures, with an outline of how it can readily be extended to the n-port case     

A Desktop Analysis of Potable Water Savings from Internally Plumbed Rainwater Tanks in South-East Queensland,Australia

A methodology for the estimation of household potable water saving due to internally plumbed rainwater tanks (IPT) is presented in this paper. The methodology is based on a pairwise comparison of household water billing data between homes with IPT and without rainwater tanks (No Tank). These savings were compared with estimations using measured end use data and rainwater demand predictions using the Rainwater TANK model. The paper describes the application of this methodology to a case study in the south-east Queensland (SEQ) region of Australia. There was a significant reduction in mains water consumption for IPT properties in all regions studied in SEQ. Water reductions from mains supplies varied markedly across regions with mean values ranging from 20 to 95 kL/hh/y with an average mean of 50 kL/hh/y. Median water consumption values, ranged in mains water reductions from 28 to 52 kL/hh/y, with an average median of 40 kL/hh/y. Considering both measures an average water saving between 40 and 50 kL/hh/y can be expected from internally plumbed rainwater tanks. Water restrictions appear to have a strong influence on estimated reductions in mains water use. In regions where water restrictions were severe, water consumption was less varied between No Tank and IPT homes with a consequent reduction in estimated savings observed. Recommendations for further work include a survey to capture confounding factors that could not be fully controlled in the desktop study and a controlled pairwise experiment to monitor water consumption from raintanks.