Spray drying is a process in which a liquid containing dissolved or suspended solids is injected into a chamber through a spray nozzle or centrifugal disk atomizer. The resulting mist is contacted with hot air, which evaporates most or all of the liquid, leaving the dried solids to fall to a conveyor belt at the bottom of the chamber. Inlet air .1 Dried milk -- Wet air 311 m3/min @ 83C, 1 atm Student Workbook Encyclopedia Equipment nozzle 217 Powdered milk is produced in a spray dryer 6 m in diameter by 6 m high. Air enters at 167C and -40 em H2O. The milk fed to the atomizer contains 70% water by mass, all of which evaporates. The outlet gas contains 12 mole% water and leaves the chamber at 83C and 1 atm (absolute) at a rate of 311 m3/min. (a) Calculate the production rate of dried milk and the volumetric flow rate of the inlet air. Estimate the upward velocity of air (m/s) at the bottom of the dryer. (b) What problem would you guess would occur if the velocity is too high?
Exam 2 study guide for CDFS 111 1. Self concept •A person’s understanding of who he or she is, incorporating selfesteem, appearance, personality, and various traits (e.g. gender, size). SelfEsteem confidence in one's own worth or abilities; selfrespect 2. Motivation: Extrinsic Occurs when people do something to gain praise or some other reinforcement. Intrinsic –Occurs when people do something for the joy of doing it. 3. Baumrind and Dimensions of Parenting •Authoritarian parenting: High behavioral standards, strict punishment of misconduct, and little communication •Permissive parenting: High nurturance and communication but little discipline, guidance, or control •Authoritative parenting: Parents set limits and enforce rules but are flexible and listen to their children •Neglectful/uninvolved parenting: Parents are indifferent toward their children and unaware of what is going on in their children’s lives Children of authoritarian parents tend to •become conscientious, obedient, and quiet but not especially happy •feel guilty or depressed and blame themselves when things don’t go well •rebel as adolescents and leave home before age 20 Children of permissive parents tend to: •be unhappy and lack selfcontrol, especially in peer relationships •suffer from inadequate emotional regulation •be immature and lack friendships (main reason for their unhappiness) •continue to live at home, still dependent, in early adulthood Children of authoritative parents tend to: •be successful, articulate, happy with themselves, and generous with others •be wellliked by teachers and peers, especially in societies in which individual initiative is valued Children of uninvolved parents tend to: •be immature, sad, lonely and at risk of abuse •may have social and cognitive problems 4. Erikson’s stage between 3 and 6 years •Trust versus mistrust –Infants learn basic trust if the world is a secure place where their basic needs are met •Autonomy versus shame and doubt –Toddlers either succeed or fail in gaining a sense of selfrule over their actions and their bodies Initiative vs Guilt 5. Parenting Styles Diana Baumrind (1967, 1971). Parents differ on four important dimensions: 1.Expressions of warmth: From very affectionate to cold and critical 2.Strategies for discipline: Parents vary in whether and how they explain, criticize, persuade, ignore, and punish. 3.Communication: Some parents listen patiently to their children; others demand silence. 4.Expectations for maturity: Parents vary in the standards they set for their children regarding responsibility and selfcontrol. 6. Nutrition •Children need far fewer calories per pound of body weight than infants do. •Obesity is a more frequent problem than malnutrition. against undernutrition and parents may rely on fast foods. to obesity cultures still guard •Overfeeding is causing an epidemic of illnesses associated with obesity –Such as heart disease and diabetes Tooth Decay –most common disease of young children in developed nations •Affects more than onethird of all children under age 6 in the United States Too much sugar and too little fiber rot the teeth Just Right •Some children only eat certain foods, prepared and presented in a particular way. –Would be pathological in adults but is normal in children under 6. •The responses of 1,500 parents surveyed about their 1 to 6yearolds (Evans et al., 1997) indicated that over 75% of the 3yearolds evidenced some justright tendency, they: –preferred to have things done in a certain order or way –had a strong preference to wear (or not wear) certain clothes –prepared for bedtime by engaging in a special activity or routine –had strong preferences for certain foods 7. Limbic System •Amygdala A tiny brain structure that registers emotions, particularly fear and anxiety. locations.us A brain structure that is a central processor of memory, especially memory for •Hypothalamus A brain area that responds to the amygdala and the hippocampus to produce hormones that activate other parts of the brain and body. Cortex outer layers of the brain in humans and other mammals. Most thinking, feeling, and sensing involve the cortex (sometimes called neocortex) Corpus Callosum•a band of nerve fibers that connects the left and right sides of the brain, grows and myelinates rapidly during early childhood. efficient. the corpus callosum makes communication between the two brain hemispheres more Myelination Myelin is a fatty coating on the axons that speeds signals between neurons. •A gradual increase in myelination makes 5yearolds much quicker than 3yearolds, who are quicker than toddlers. Prefrontal cortex area of cortex at the front of the brain that focuses in anticipation, planning, and impulse control. •From ages 2 to 6, maturation of the prefrontal cortex has several notable benefits: –sleep becomes more regular –emotions become more nuanced and responsive –temper tantrums subside 8. Gross motor skills Physical abilities involving large body movements, like walking and jumping. “Gross” means big in this term here Fine motor skills •More difficult to master than gross motor skills •Many involve two hands and both sides of the brain •Typically mature about 6 months earlier in girls than boys 9. Kinship Care •A form of foster care in which a relative of a maltreated child, usually a grandparent, becomes the approved caregiver. Foster Care maltreated child is removed from the parents’ custody and entrusted to another adult or family, which is reimbursed for expenses incurred in meeting the child’s needs 10. Animism Belief that objects and phenomena are alive Egocentrism Piaget's term for kid’s tendency to think about the world entirely from their own personal perspective Guided Participation In sociocultural theory, a technique in which skilled mentors help novices learn not only by providing instruction but also by allowing direct, shared involvement in the activity. (also called apprenticeship of learning) 11. Overregularization Application of rules of grammar even when exceptions occur •Makes language seem more “regular" than it actually is 12. Head Start • Most widespread earlychildhood education program in the United States •Begun in 1965 and funded by the federal government •Initially, the program was thought to be highly successful at raising children's intelligence; ten years later, early gains were found to fade Reggio Emilia encourages each child’s creativity in a carefully designed setting Montessori a system of education for young children that seeks to develop natural interests and activities rather than use formal teaching methods. •emphasize individual pride and accomplishment, presenting literacyrelated tasks (such as outlining letters and looking at books). Teacherdirected Stress academic subjects taught by a teacher to an entire class •Help children learn letters, numbers, shapes, and colors, as well as how to listen to the teacher and sit quietly •Make a clear distinction between work and play •Are much less expensive, since the child/adult ratio can be higher 13. Zone of proximal development •Skills that a person can exercise only with assistance, not yet independently Private speech internal dialogue that occurs when people talk to themselves (silently or out loud) Scaffolding •Temporary support that is tailored to a learner's needs and abilities and aimed at helping the learner master the next task in a given learning process 14. Fast mapping •Speedy and sometimes imprecise way in which children learn new words by tentatively placing them in mental categories according to their perceived meaning 15. Reversibility •Characteristic of preoperational thought whereby a young child thinks that nothing can be undone. A thing can sometimes be restored to the way it was before a change occurred. Focus on Appearance A characteristic of preoperational thought in which a young kid ignores all attributes that are not apparent TheoryTheory •Children attempt to explain everything they see and hear. Children develop theories about intentions before they employ their impressive ability to imitate. 16. Center of Gravity •moves from the breastbone down to the belly button.