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Gas-lift is a strategy to enhance oil production from oil wells by reducing the hydrostatic pressure of the fluid. Efficient modeling of this process is a key point for the oil and gas industry to maximize oil output while minimizing gas consumption. This study introduces a novel hybrid model for the gas-lift process, using the Universal Differential Equation (UDE) approach. Neural networks replace algebraic equations, trained based on physical laws. The UDE method eliminates dependence on unmeasured variables, enhancing accuracy. Tested with simulated data, the hybrid model outperforms traditional models, demonstrating effective prediction of state variables and Efficient handling of algebraic variables. This approach holds promise for gas-lift process modeling, control, and optimization.

Waxy wheat (Triticum aestivumL.) is grown throughout the world for its specific quality. Fertilization and planting density are two crucial factors that affect waxy wheat yield and photosynthetic capacity. The objectives of the research were to determine the effects of fertilization and planting density on photosynthetic characteristics, yield, and yield components of waxy wheat, including Yield, SSR, TGW, GNPP, GWPP, PH, HI, Pn, Gs, Ci, E and WUE using the method of field experiment, in which there were three levels (150, 300, and 450 kg ha–1) of fertilizer application rate and three levels (1.35, 1.8, and 2.25 × 106plants ha–1) of planting density. The results suggested that photosynthetic characteristics, yield, and yield components had close relationship with fertilization levels and planting density. Under the same plant density, with the increase of fertilization, Yield, SSR, TGW, GNPP, GWPP, HI, Pn, Gs, E and WUE increased and then decreased, PH increased, but Ci decreased. Under the same fertilization, with the increase of plant density, Yield, SSR, TGW, GNPP, GWPP, HI increased and then decreased, PH, Pn, Gs and E increased, PH and WUE declined. The results also showed that F2 (300 kg ha–1) and D2 (1.8 × 106plants ha–1) was a better match in this experiment, which could obtain a higher grain yield 4961.61 kg ha–1. Consequently, this combination of fertilizer application rate and plant densities are useful to get high yield of waxy wheat.

The synthesis, structures, and reactivity of new lanthanocene complexes incorporating amidinate ligand [^tBuN&bondDotb;C(ⁿBu)&bondDotb;N^tBu] are described. Treatment of Cp2LnⁿBu (Ln = Er (1), Y (2), Gd (3)) with N,N‘-di-tert-butylcarbodiimide results in monoinsertion of carbodiimide into the Ln−C σ-bond to yield the title compounds Cp2Ln[^tBuN&bondDotb;C(ⁿBu)&bondDotb;N^tBu] (Ln = Er (4), Y (5), Gd (6)). Complexes 4−6 were characterized by elemental analysis and IR and mass spectroscopies. The structures of complexes 4 and 5 were determined through X-ray single-crystal diffraction analysis. It is shown that compound 5 is a fine catalyst for cyclotrimerization of phenyl isocyanate.

Separate magnetic resonance images of water and fat of oil-in-water emulsions and cheese blocks were obtained using the chemical shift selective suppression technique. With this technique, the proton signals emitted from water can be readily separated from those emitted from fat in the same sample through a single experiment using magnetic resonance imaging. Relaxation compensation was made to improve the quality of suppression. The experiment using oil-in-water emulsions demonstrated an excellent linear relationship between the intensity of the signal and the concentrations of water or fat. Images of a cheese slice showing only water or fat revealed that moisture distribution was less uniform than was fat distribution. Moisture contents determined by the magnetic resonance imaging technique were very close to those obtained by the oven-drying method.

The changes in hardness and molecular mobility of water of cooked wild rice during 10 days storage were investigated in this study. Seven grades of wild rice were subjected to various degrees of soaking and cooking and were stored at 5C. Nuclear magnetic resonance (NMR) technique was employed to determine the free induction decay (FID) signals and spin‐spin relaxation time constants (T2) of protons, which was regarded as a measure of rotational molecular mobility of water in the samples. Multi‐component behavior of FID signals was observed, based on which water molecules in the samples were classified into three fractions with different T2s. The hardness of the samples was assessed using a texture analyzer. All samples firmed over the storage period, which correlated well with the changes in NMR parameters. A multiple variable regression model was proposed to describe the relationships between firming and NMR parameters in the wild rice samples. The model demonstrates the possibility of using NMR parameters to assess and predict the firmness of the samples during storage.

Temperature-sensitive hydrogels swell and collapse reversibly in aqueous solution. The hydrogel process is a different form of ultrafiltration and has been used to separate biological molecules. In this study, the gel pore size was predicted by pulse NMR technique and neural network using a data base obtained from gel filtration chromatography and diffusion experiment.

Plant cell culture of Coleus blumeiwhen entrapped in temperature-sensitive hydrogel beads [poly(N-isopropylacrylamide) containing 0.5% alginate], retained viability during the three weeks culture. Test also indicated that the hydrogel beads (containing 0.5% alginate) with immobilized cells were still temperature sensitive in aqueous solution.

Non-destructive Magnetic Resonance Imaging (MRI) techniques were developed to monitor simultaneous heat and moisture transfer in cheese cooling. The FLASH imaging sequence was used to achieve fast data acquisition for temperature images. MRI results of temperature distributions in cheese blocks during cooing are very closed to those from numerical simulation.

Numerical simulation method was developed and used to predict temperature and moisture distribution in large Cheddar cheese block during cooling based on a simultaneous heat and mass transfer model. The predicted results agreed well with the experimental results. The results suggest that cooling for 3 to 4 days would be sufficient to achieve fairly uniform distribution of temperature and moisture in a 640 lb Cheddar cheese block.

Two barley cultivars, Excel and Prisma (six-row and two-row types, respectively), were obtained from the 1993 harvest at Crookston, MN. Magnetic resonance imaging (MRI) was used to follow water imbibition in single, large seeds of Excel and Prisma barley. A comparison of moisture distribution on longitudinal sections of Prisma and Excel barley during early hours of steeping was then made. MRI analysis revealed that the majority of water initially entered the kernel through the kernel surfaces and into the endosperm tissues. Water was observed under the surface of the hull tissues and appeared to be migrating into the aleurone and endosperm tissues. Then water was detected moving from the embryo to the scutellum and then into the crushed cell layers. Aleurone and embryo tissue showed more rapid water uptake and distribution than did scutellar tissue. Some transient water distribution was observed in the scutellum, ventral furrow, and vascular tissues. This indicates that the hydration of surface tissues and crushed cell layers may be significant during the early hours of steeping. During the late hours of steeping, the crushed cell and endosperm cavity region appears to become remarkably active in water transport. Water was distributed throughout the endosperm tissue of the Prisma cultivar more efficiently than in that of the Excel cultivar, although Excel absorbed more water initially.

The mobility of water in bread stored at 5 and 22 °C was studied using nuclear magnetic resonance (NMR) relaxation techniques. A multi-component model was used to analyse the proton relaxation curves, from which water in the bread crumb samples was classified into three categories, each of which had a distinct relaxation time (T2) or molecular mobility. The changes in crumb firmness, T2and proton intensity (A) of the three categories of water in the crumb were monitored during storage. It was found that several NMR parameters correlated with the firming process in the bread crumb (1), and could be related to macroscopic and microscopic migration of water during staling.

MRI techniques were developed and employed for non-destructive and noninvasive study of seedcoat cracking in low moisture soybean kernels during heated air drying. Proton density image and transient moisture distribution profile of a single soybean kernel can be obtained using MRI. These MRI techniques proved to be particularly useful for the continuous observation of initiation and propagation of seedcoat cracking during the entire period of drying process without interruption.The proton density images of soybean kernels showed that seedcoat cracking was initiated perpendicular to the long axis of the kernel near the hilum. The transient moisture distribution profiles in soybean kernels during drying indicate that moisture gradient developed during drying was higher in the seedcoat than in the cotyledon. Drying temperature and initial average moisture content were positively correlated with the soyhean seedcoat crackig. The location of the

In this study, seedcoat cracking during heated air drying was investigated in five varieties of Minnesota grown soybeans. Effects of initial moisture contents, drying temperatures and time on cracking levels were evaluated. Digital image analysis (DIA) was employed to measure initial sizes and shapes of soybeans in order to evaluate the influence of physical properties of mature seeds on cracking frequency.Seedcoat cracking rates increased significantly with increase in initial moisture content of the soybeans. drying temperature and time. Rapid water loss at higher initial moisture contents led to greater seedcoat cracking. Variety.growing location. and sizc of soybeans had significant influence on seedcoat cracking. Statistical analysis indicates that interactions between various factors had significant influence on seedcoat cracking.

Nitric oxide synthase activities in the facial motor nucleus were studied in rats after unilateral compression of the facial nerve. Using a radiometric assay which measured the total soluble nitric oxide synthase activities in the facial motor nucleus and the surrounding tissues, it was found that nitric oxide synthase activities were markedly increased during facial paralysis that resulted from compression of the facial nerve. The subsequent decrease in nitric oxide synthase activities between postoperative days 20 and 40 coincided with the recovery of facial functions. In contrast, staining with NADPH-diaphorase histochemistry revealed that the diaphorase activities in the facial motor neurons were markedly increased between days 20–40 when the total activities as measured biochemically were in decline. However, staining of the vascular endothelium was increased on postoperative day 7 when the total activity was high. It is suggested that the increase in total nitric oxide synthase activities immediately after facial nerve compression may be predominantly endothelial. Since the increase in neuronal NADPH-diaphorase reactivity coincided with the recovery of facial functions, increased neuronal nitric oxide synthase may be a contributing factor to the restoration of facial innervation.

The development of somatic embryos is characterized by a series of morphological changes. Quantitative kinetic studies have been hampered by the difficulties in enumerating and characterizing embryo populations. By employing neural networks, we have developed a pattern-recognition system for characterizing the morphological features of carrot somatic embryos. This pattern-recognition system employs a hierarchical decision tree to achieve optimal classification. It successfully classified carrot somatic embryos into normal and abnormal embryo classes. For normal embryo classes (globular, oblong, heart, and torpedo embryos), an accuracy of 90% or higher was achieved. The features identified by the neural network classifiers as most important for embryo classification are almost identical to those obtained by the branch-and-bound searching algorithm used previously. However, employing the neural networks shortens the system developing time greatly. Coupled with an image analysis system, this neural-network-based pattern-recognition system shows great potential in embryo sorting and automation of synthetic seed production.

The proton relaxation behavior of a temperature-sensitive gel, observed through using a pulse NMR technique, was related to the structural characteristics of the gel. As the temperature increased, the pore size of the gel decreased gradually while the relaxation time constants, T and T, showed different patterns of change. It is believed that the proton relaxation was affected by a direct temperature effect and an indirect, temperature-related structural effect. The response of the protons to these effects varied depending on where the protons resided. A sudden increase in several NMR parameter values occurred at around 30°C, the lower critical solution temperature (LCST). This may be related to a transition state of the gel undergoing dramatic local non-uniform changes around the LCST. [ABSTRACT FROM AUTHOR]

Use of microalgae in agricultural application has substantially increased in recent years. To evaluate the relative nutritional value of microalgae products, it is necessary to have an estimate of the nutrient digestibility. In vitro procedures are a good alternative to model processes of nutrient digestion in the gastrointestinal tract of pigs. The objective of this project was to measure the nutrient composition and in vitro DM digestibility (IVDMD) of different microalgae sources. Four microalgae samples were obtained from multiple agricultural sources: 1) microalgae (Chlorellasp.) grown in waste water from a dairy processing plant, 2) microalgae (Chlorellasp.) grown in waste water from a meat processing plant, 3) protein and lipid extracted microalgae product grown for biofuels production, and 4) microalgae (Pavlovasp.) grown in microalgae-specific media. The IVDMD was measured using a 2-step technique. First, triplicate samples from each source (1 g) were incubated in a 7:1 mixture of potassium phosphate– and sodium phosphate–based buffer solutions (pH 2) with 2 mL (100 mg/mL) of fresh pepsin solution for 2 h at 39°C. Immediately after gastric hydrolysis, small intestinal hydrolysis was performed by adjusting solution pH to 6.8 by adding a 1:1 mixture of potassium phosphate– and sodium phosphate–based buffer solutions and adding 2 mL of pancreatin solution (100 mg/mL). After 4 h of hydrolysis at 39°C, all samples were centrifuged at 10,000 g for 10 min and supernatant was removed. The pellet after centrifugation was dried at 55°C for 48 h and the weight was recorded. The IVDMD was calculated as a ratio between DM before and after hydrolysis. The IVDMD of Pavlovasp. (50.7 ± 0.5%) was less (P< 0.05) than that of Chlorellasp. grown in dairy waste water (57.1 ± 0.1%), which was greater than that of Chlorellasp. grown in meat processing waste water (64.2 ± 0.9%). The greatest IVDMD was observed in the protein and lipid extracted microalgae product (80.2 ± 4.9%). Digestibility values of microalga grown in dairy waste water and grown in meat processing waste water were not different (P> 0.05) from ground corn (62.6 ± 2.7%) used as control. In conclusion, microalgae products from various industrial application may have significantly different nutritional values to growing pigs because they have different digestibility values.

The present study is concerned with physical and chemical characterization of polysaccharides in fresh lilies. Plant polysaccharides have been found to have many clinical benefits, including lowering blood sugars. Consumption of fresh lilies as food in China and other part of the world is rapidly increasing. Understanding the physical and chemical properties of lily polysaccharides is the first step toward further clinical studies. Fresh lilies were extracted using a hot water extraction method. Several techniques were used to remove residual proteins. DEAE cellulose columns were used to purify the isolates. Paper and gas chromatography techniques were used to determine the compositions and molecular weights of the polysaccharides. Two fractions of lilypolysaccharides, namely LP1 and LP2, were obtained. It was found that LP1 contained mainly glucose and mannose (glucose:mannose = 1:2.46) with an average molecular weight of 79,400, and LP2 contained glucose, galactose, mannose, arabinose, and galacturonic acid (1:0.73:2.6:1.8:0.84) with an average molecular weight of 18,150. [ABSTRACT FROM AUTHOR]

Presents a study that examined the effects of liquid dosing, vacuum release time and pellet size on the gradient of liquid concentration between the central and the outer region of feed pellet. Review of related literature; Materials and methods used; Results and discussion.