Corn silage hybrid type and quality of alfalfa hay affect dietary nitrogen utilization by early lactating dairy cows

This experiment was conducted to determine the effects of corn silage (CS) hybrids and quality of alfalfa hay (AH) in high-forage dairy diets on N utilization, ruminal fermentation, and lactational performance by early-lactating dairy cows. Eight multiparous Holstein cows were used in a duplicated 4 × 4 Latin square experiment with a 2 × 2 factorial arrangement of dietary treatments. The 8 cows (average days in milk = 23 ± 11.2) were surgically fitted with ruminal cannula, and the 2 squares were conducted simultaneously. Within square, cows were randomly assigned to a sequence of 4 diets: conventional CS (CCS) or brown midrib CS (BMR) was combined with fair-quality AH [FAH: 46.7% neutral detergent fiber (NDF) and 18.4% crude protein (CP)] or high-quality AH (HAH: 39.2% NDF and 20.7% CP) to form 4 treatments: CCS with FAH, CCS with HAH, BMR with FAH, and BMR with HAH. Diets were isonitrogenous across treatments, averaging 15.9% CP. Each period lasted a total of 21 d, with 14 d for treatment adaptation and 7 d for data collection and sampling. Intake of DM and milk yield did not differ in response to CS hybrids or AH quality. Although feeding BMR-based diets decreased urinary N output by 24%, it did not affect fecal N output. Feeding HAH decreased urinary N output by 15% but increased fecal N output by 20%. Nitrogen efficiency [milk N (g/d)/intake N (g/d)] tended to increase for BMR treatments. Ruminal ammonia-N concentration was lower for cows fed BMR-based diets than for those fed CCS-based diets but was not affected by quality of AH. Feeding BMR-based diets or HAH decreased milk urea N concentration by 23 or 15%, respectively, compared with CCS-based diets or FAH. Total volatile fatty acid concentration increased with HAH but was not influenced by CS hybrids. Feeding BMR-based diets decreased urinary N-to-fecal N ratio (UN:FN), and it was further reduced by feeding HAH. Although cows fed the BMR-based diets tended to increase milk N-to-manure N ratio, the quality of AH did not affect the ratio. The lower ratio of UN:FN with a higher ratio of milk N-to-manure N ratio for the BMR-based diets indicates that feeding BMR may reduce manure ammonia-N by reducing excretion of urinary N and increasing secretion of milk N per unit of manure N excreted.     

Finding little Albert: A journey to John B. Watson’s infant laboratory.

In 1920, John Watson and Rosalie Rayner claimed to have conditioned a baby boy, Albert, to fear a laboratory rat. In subsequent tests, they reported that the child’s fear generalized to other furry objects. After the last testing session, Albert disappeared, creating one of the greatest mysteries in the history of psychology. This article summarizes the authors’ efforts to determine Albert’s identity and fate. Examinations of Watson’s personal correspondence, scientific production (books, journal articles, film), and public documents (national census data, state birth and death records) suggested that an employee at the Harriet Lane Home was Albert’s mother. Contact with the woman’s descendents led the authors to the individual they believe to be “Little Albert.” (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Preparation of Aluminum Coatings Containing Homogenous Nanocrystalline Microstructures Using the Cold Spray Process

Nanostructured materials are of widespread interest because of the unique properties they offer. Well-proven techniques, such as ball milling, exist for preparing powders with nanocrystalline microstructures. Nevertheless, consolidation of nanocrystalline powders is challenging and presents an obstacle to the use of nanocrystalline metals. This work demonstrates that nanocrystalline aluminum powders can be consolidated using the cold spray process. Furthermore, transmission electron microscopy (TEM) analysis of the nanocrystalline cold spray coatings reveals that the cold spray process can cause significant grain refinement. Inert gas atomized 6061 and 5083 aluminum powders were ball milled in liquid nitrogen resulting in micron-sized powder containing 250-400 nm grains. Cold spray coatings prepared using these feed stock materials exhibited homogenous microstructures with grain sizes of 30-50 nm. TEM images of the as-received powders, ball-milled powders, and cold spray coatings are shown.     

Film rupture model for aqueous stress corrosion cracking under constant and variable stress intensity factor

A film rupture model for aqueous stress corrosion cracking is developed and used to predict kinetics of crack growth under constant and variable stress intensity factor. The model predicts that creep is necessary for sustained crack growth and creep rate limits crack velocity for constant K and dK/da loading. Contrary to recent thinking, the crack tip strain due to crack advance is viewed as a result, not a cause of crack growth. The crack tip strain gradient elevates and maintains crack tip stress as the crack propagates, which enables creep and sustained crack growth. The model provides a basis for understanding effects of positive and negative K - variation on crack growth.     

Force Transmission Error Analysis for a High-Pressure Single-Sinker Magnetic Suspension Densimeter

The magnetic suspension densimeter (MSD) is a sophisticated, state-of-the-art device that provides extremely accurate results for density measurements. The MSD uses a magnetic technique to couple a mass inside a measurement cell with an external mass balance for mass measurement. This article presents a force transmission error (FTE) analysis for a high-pressure, single-sinker MSD. Due to the magnetic working principle of the apparatus, magnetic properties of the high-pressure cell and external magnetic fields affect the measurements slightly. For the analysis, McLinden et al. suggest making measurements using two different sinkers, a titanium sinker and a copper sinker, having the same mass. The measurements cover densities for methane, ethane, carbon dioxide and nitrogen over the temperature range from 265 K to 450 K (±5 mK stability) up to 180 MPa (uncertainty of 0.01 % full scale: 200 MPa). Comparing and manipulating the measurements permit determination of apparatus and fluid specific effects that contribute to the FTE. For this MSD, the apparatus effect is about 200 ppm, which effectively masks any fluid specific effect. A comprehensive analysis of the FTE produces a uniform deviation for density values of about 0.05 % at 2σ across the full range of pressure.     

Three-dimensional millimeter-wave imaging for concealed weapondetection

Millimeter-wave imaging techniques and systems have been developed at the Pacific Northwest National Laboratory (PNNL), Richland, WA, for the detection of concealed weapons and contraband at airports and other secure locations. These techniques were derived from microwave holography techniques that utilize phase and amplitude information recorded over a two-dimensional aperture to reconstruct a focused image of the target. Millimeter-wave imaging is well suited for the detection of concealed weapons or other contraband carried on personnel since millimeter-waves are nonionizing, readily penetrate common clothing material, and are reflected from the human body and any concealed items. In this paper, a wide-bandwidth three-dimensional holographic microwave imaging technique is described. Practical weapon detection systems for airport or other high-throughput applications require high-speed scanning on the order of 3 to 10 s. To achieve this goal, a prototype imaging system utilizing a 27-33 GHz linear sequentially switched array and a high-speed linear scanner has been developed and tested. This system is described in detail along with numerous imaging results     

High velocity flyer plate launch capability on the Sandia Z accelerator

A method has been developed for launching plates useful for equation of state (EOS) studies to high velocities using fast pulsed power on the Sandia National Laboratories Z Accelerator. The technique employs magnetic pressure developed in an insulating gap between the anode and cathode of the machine to provide smoothly increasing, quasi-isentropic loading to plates of 9 – 12 mm in diameter and hundreds of microns thickness. Successful launches of titanium to 12km/s, aluminum to 13km/s, and copper to 10km/s have been demonstrated. The plates were monitored through the entire launch process with both conventional and spatially resolved velocity interferometry to obtain acceleration histories and impact profiles. Impacts of the flyers into aluminum wedges were also performed to experimentally estimate final plate thickness. Initial indications are that the plates are intact, slightly bowed, and at essentially ambient state.     

漂白剂和表面活性剂的混合(英)

烷基二酚醚二磺酸盐表面活性剂可以很好地和漂白剂次氯酸钠混合 ,在含次氯酸钠的配方中 ,稳定性和溶解性均很好 ,不会促使漂白剂分解。     

The Al(L) + AlB12 ? AlB2 peritectic transformation and its role in the formation of high aspect ratio AlB2 flakes

A new family of metal matrix composites (MMCs) based on high aspect ratio AlB₂ is being developed. Preparation of these MMCs involves the conversion of low aspect ratio AlB₂ to high aspect ratio AlB₂. This conversion is associated with the Al_(L) + AlB₁₂ ↔ AlB₂ peritectic transformation. There is confusion surrounding the temperature at which this transformation occurs. Its value has been reported as high as 1,500 °C and as low as 980 °C. In this paper, the peritectic temperature has been investigated using calorimetric methods and determined to be 956 ± 5 °C. In addition, an unexpected conversion of low aspect ratio AlB₂ to high aspect ratio AlB₂ has been identified near the peritectic temperature.     

Effects of elevated operating temperatures on methanol removal kinetics from synthetic kraft pulp mill condensate using a membrane bioreactor

The feasibility of biologically removing methanol from kraft pulp mill evaporator condensate was investigated, using a high temperature membrane bioreactor (MBR). Over the range of temperatures investigated (55–70°C), a mixed culture of methanol-utilizing microorganisms could be successfully developed, using synthetic condensate as a feedstock. A maximum specific methanol utilization coefficient of approximately 0.81 day⁻¹ occurred at an operating temperature of 60°C. Over 99% of the methanol was removed from the condensate at operating temperatures of 55 and 60°C. Above 60°C, the specific methanol utilization coefficient declined sharply, indicating that at high operating temperatures, the inactivating effect of temperature on the mixed culture of microorganisms must be considered. A relatively simple model was proposed and used to estimate the effect of high temperatures on methanol removal kinetics in an MBR over the range of temperatures investigated. The operating temperature also had a significant effect on the observed growth yield. At increasing operating temperatures, a larger fraction of the methanol consumed was converted to energy, reducing the observed growth yield.