List four substances in water having deleterious effects. State their effects on concrete.

List four substances in water having deleterious effects. State their effects on concrete.
by

1 Answer

Answer :

Substances in water:

1. Suspended particles

2. Inorganic salts

3. Acids and Alkalis

4. Algae

5. Sugar content

6. Mineral oil

Effects of deleterious materials on concrete: 

1. Suspended particles: If the mixing of water contains suspended particles more than 0.02% by weight of total water un concrete, then it affects all properties other than strength of concrete. 

2. Inorganic salts: The inorganic salts like zinc chloride lead nitrate, sodium phosphate etc. reduces strength whereas sodium and potassium carbonates results very rapid setting of concrete. The presence of calcium chloride in water more than 1.5% of total weight of cement results reduces rate of setting of concrete. The salt content in sea water reduces the concrete strength about 10-20% and also affects curing in the form of efflorescence. 

3. Acids and Alkalis: The acids and alkalis present in industrial waste water results in undesirable alkaliaggregate reaction giving cracks on concrete surface. 

4. Algae: The algae present in water reduces bond between 

5. Cement and aggregate: hence reduces strength of concrete. 

6. Sugar  The sugar content in water between 0.05- 0.15% by weight of water results in retarding setting time and early strength of concrete. The sugar more than 0.20% will give fast setting but reduces ultimate strength of concrete. 

7. Oil  Mineral oil more than 8% reduces strength of concrete and vegetable oil shows detrimental effects on concrete strength at its later stages.
by

Related questions

The complement system consists of a series of serum proteins that exist in a quiescent or very low-level state of activation in the uninfected host. Which of the following statement(s) is/are true concerning complement activation? a. The alternate (properdin) pathway of complement activation can occur directly through contact with fungal or bacterial cell wall compounds b. Complement component fragments may serve to decrease vascular permeability c. Excessive complement activation can produce deleterious effects d. Fragments of certain complement components serve as chemoattractants to additional cellular components of the host defense mechanism

Description : The complement system consists of a series of serum proteins that exist in a quiescent or very low-level state of activation in the uninfected host. Which of the following ... certain complement components serve as chemoattractants to additional cellular components of the host defense mechanism

Last Answer : Answer: a, c, d Complement activation can occur through either classic or alternate (properdin) pathways, both of which eventuate in deposition of terminal complement pathway components on the ... and release of lysosomal enzymes that can directly damage certain target tissues, such as the lung

Which of the following statements are true of oxidants? A. In addition to their pathophysiologic roles in inflammation, injury, and infection, oxidants also have physiologic roles. B. Oxidants may be generated from activated neutrophils and during reperfusion following a period of ischemia. C. The deleterious effects of oxidants include lipid peroxidation and cell membrane damage, oxidative damage to DNA, and inhibition of adenosine triphosphate (ATP) synthesis. D. The mechanism of ischemia-reperfusion injury involved the catalytic production of superoxide anion (O 2•) by the enzyme xanthine oxidase.

Description : Which of the following statements are true of oxidants? A. In addition to their pathophysiologic roles in inflammation, injury, and infection, oxidants also have physiologic roles. B. Oxidants may ... involved the catalytic production of superoxide anion (O 2 ) by the enzyme xanthine oxidase.

Last Answer : Answer: ABCD DISCUSSION: Oxidants are reactive oxygen metabolites that have both physiologic and pathophysiologic roles. As potent oxidizing agents, oxidants are involved in cytochrome P ... leukocyte infiltration and activation, causing further tissue damage by the release of cytotoxic proteases

The deleterious materials present in the aggregate (a) Prevent normal hydration of cement (b) Reduce the strength and durability of concrete. (c) Modify the setting action and cause efloresecence. (d) All of the above

Description : The deleterious materials present in the aggregate (a) Prevent normal hydration of cement (b) Reduce the strength and durability of concrete. (c) Modify the setting action and cause efloresecence. (d) All of the above

Last Answer : (d) All of the above

Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and actions of cytokines? a. Cytokines are produced solely by macrophages b. Cytokines act only on other cells within the same local environment c. Cytokines may have both protective and deleterious effects on the host d. Each specific cytokine is produced by a single cell type

Description : Cytokines are low-molecular-weight polypeptides exerting a wide variety of biologic effects at both local and systemic levels. Which of the following statement(s) is/are true concerning the production and ... effects on the host d. Each specific cytokine is produced by a single cell type

Last Answer : Answer: c Macrophages, endothelial cells, lymphocytes, and other cells secrete a large number of different compounds, termed cytokines, that are most probably evolved for the purpose of ... host defenses, exerting both salutatory and deleterious effects on the host, has become increasingly evident

Increasing evidence has implicated gram-negative bacterial lipopolysaccharide (LPS endotoxin) as the portion of the gram-negative bacterial cell membrane responsible for many, if not all the toxic effects that occur during gram-negative bacterial sepsis. The following statement(s) is/are true concerning LPS and the host response. a. The LPS molecule can in itself cause physiologic responses similar to that seen during gram-negative bacterial sepsis b. LPS triggers host macrophages to release a variety of cytokines including TNF-a, IL-1a, and IL-1b, IL-6, and IFN-a c. Excessive cytokine production is not associated with detrimental consequences d. TNFa and IL-1b appear to be the primary mediators within the host, exerting deleterious effects on the host when excessive amounts reach the syst

Description : Increasing evidence has implicated gram-negative bacterial lipopolysaccharide (LPS endotoxin) as the portion of the gram-negative bacterial cell membrane responsible for many, if not all the ... host, exerting deleterious effects on the host when excessive amounts reach the systemic circulation

Last Answer : Answer: a, b, d The LPS molecule exerts diverse effects on the mammalian host. Immunologic responses to LPS include nonspecific polyclonal B-cell proliferation, macrophage activation and ... deleterious effects on the host only after large amounts are secreted and reach the systemic circulation

Presence of __________ in water stream are deleterious to aquatic life. (A) Soluble and toxic organics (B) Suspended solids (C) Heavy metals and cyanides(D) All (A), (B) & (C)

Description : Presence of __________ in water stream are deleterious to aquatic life. (A) Soluble and toxic organics (B) Suspended solids (C) Heavy metals and cyanides (D) All (A), (B) & (C)

Last Answer : (D) All (A), (B) & (C)

A : EI Nino is a climatic change which causes deleterious environmental changes. R : Increased trophospheric ozone due to El Nino cause shift of clima

Description : A : EI Nino is a climatic change which causes deleterious environmental changes. R : Increased trophospheric ozone due to El Nino cause shift of clima

Last Answer : A : EI Nino is a climatic change which causes deleterious environmental changes. R : Increased trophospheric ... and Reason are false, then mark (4).

Whoever places in or against any letter box provided by the post office for the reception of postal articles any fire, match or light, any explosive, dangerous, filthy, noxious or deleterious substance a) Punishable with fine which may extend to hundred rupees and 1 month imprisonment b) Punishable with imprisonment for a term which may extend to one year or with fine or with both. c) Punishable with fine which may extend to two hundred rupees d) None of these

Description : Whoever places in or against any letter box provided by the post office for the reception of postal articles any fire, match or light, any explosive, dangerous, filthy, noxious or deleterious substance a ... with both. c) Punishable with fine which may extend to two hundred rupees d) None of these

Last Answer : c) Punishable with fine which may extend to two hundred rupees

The basis for use of β-adrenergic blockers in congestive heart failure (CHF) is: A. They exert positive inotropic effect in CHF B. They counteract deleterious effect of sympathetic overactivity on the myocardium C. They exert antiischaemic effect on the heart D. They prevent cardiac arrhythmias

Description : The basis for use of β-adrenergic blockers in congestive heart failure (CHF) is: A. They exert positive inotropic effect in CHF B. They counteract deleterious effect of sympathetic overactivity on the myocardium C. They exert antiischaemic effect on the heart D. They prevent cardiac arrhythmias

Last Answer : B. They counteract deleterious effect of sympathetic overactivity on the myocardium

The basis for use of β -adrenergic blockers in congestive heart failure (CHF) is: A. They exert positive inotropic effect in CHF B. They counteract deleterious effect of sympathetic overactivity on the myocardium C. They exert antiischaemic effect on the heart D. They prevent cardiac arrhythmias

Description : The basis for use of β -adrenergic blockers in congestive heart failure (CHF) is: A. They exert positive inotropic effect in CHF B. They counteract deleterious effect of sympathetic overactivity on the myocardium C. They exert antiischaemic effect on the heart D. They prevent cardiac arrhythmias

Last Answer : B. They counteract deleterious effect of sympathetic overactivity on the myocardium

Explain four effects of hot weather on concrete.

Description : Explain four effects of hot weather on concrete.

Last Answer : Effects of hot weather on concrete: i. Due to hot weather, concrete shows rapid rate of hardening, which results difficulty in transportation of concrete. ii. Water from concrete mix gets ... . Air entrained in concrete may get expelled due to temperature, hence workability may reduce additionally.

Name the substances responsible for greenhouse effects

Description : Name the substances responsible for greenhouse effects

Last Answer : Name the substances responsible for greenhouse effects

List four materials used for filling joints in concrete.

Description : List four materials used for filling joints in concrete.

Last Answer : Materials used for filling joints; 1. Asphalt, tar, bituminous materials 2. Fibre and fibre products 3. Sponge rubber 4. Cork 5. Polymer 6. Thermoplastic 7. Glass

List out any four effects of electric current used in measuring instruments & write name of meter working on it.

Description : List out any four effects of electric current used in measuring instruments & write name of meter working on it.

Last Answer : Effects of Electric Current used in measuring instruments:  1. Magnetic Effect: PMMC and Moving Iron type Ammeters, voltmeter and Dynamometer type wattmeters etc.  2. Electromagnetic induction ... . Electrostatic effect: Voltmeters.  5. Hall Effect: Flux meter, Poynting vector wattmeter.

List any four effects employed in measuring instruments.

Description : List any four effects employed in measuring instruments.

Last Answer : Effects Employed in Measuring Instruments: 1. Magnetic Effect 2. Electromagnetic induction 3. Heating effect 4. Electrostatic effect 5. Hall Effect 

The factors which effects the design of concrete mix is (a) Fineness modulus (b) Water cement ratio (c) Slump (d) All of these

Description : The factors which effects the design of concrete mix is (a) Fineness modulus (b) Water cement ratio (c) Slump (d) All of these

Last Answer : (d) All of these

Identify the substances having glycosidic bond and peptide bond, respectively in their structure. (a) Chitin, cholesterol (b) Glycerol, trypsin (c) Cellulose, lecithin (d) Inulin, insulin

Description : Identify the substances having glycosidic bond and peptide bond, respectively in their structure. (a) Chitin, cholesterol (b) Glycerol, trypsin (c) Cellulose, lecithin (d) Inulin, insulin

Last Answer : (d) Inulin, insulin

Air entrainment in the concrete increases (A) Workability (B) Strength (C) The effects of temperature variations (D) The unit weight

Description : Air entrainment in the concrete increases (A) Workability (B) Strength (C) The effects of temperature variations (D) The unit weight

Last Answer : (A) Workability

What is the hormone like substance Give me the list of these substances?

Description : What is the hormone like substance Give me the list of these substances?

Last Answer : An example of hormone is cortisol; the list of hormones is very long.

What are the names of the four types of substances ?

Description : What are the names of the four types of substances ?

Last Answer : The names of the four types of substances are 1. Solid matter 2. gaseous matter 3. Fluid 4. Plasma substance

Substances containing all the four elements: carbon, hydrogen nitrogen and oxygen are 1. Morphine 2. Nucleic acids 3. Starch 4. Quinine Select the correct answer by using the code below, (a) 2, 3 and 4 only (b) 1, 2 and 4 only (c) 1, 2, 3 and 4 (d) 1, 2 and 3 only

Description : Substances containing all the four elements: carbon, hydrogen nitrogen and oxygen are 1. Morphine 2. Nucleic acids 3. Starch 4. Quinine Select the correct answer by using the code below, (a) 2, 3 and 4 only (b) 1, 2 and 4 only (c) 1, 2, 3 and 4 (d) 1, 2 and 3 only

Last Answer : Ans:(b)

A coalescer in a mixer-settler liquid-liquid extraction column (A) Comprises of thin bed of substances of extended surface having high porosity (B) Helps in increasing the bubble size entering the settler (C) Helps in increasing the settling rate of the bubbles (D) All 'a', 'b', & 'c'

Description :  A coalescer in a mixer-settler liquid-liquid extraction column (A) Comprises of thin bed of substances of extended surface having high porosity (B) Helps in increasing the bubble size entering the settler ... increasing the settling rate of the bubbles (D) All 'a', 'b', & 'c'

Last Answer : (D) All 'a', 'b', & 'c'

State any four advantages and four disadvantages of precast concrete.

Description : State any four advantages and four disadvantages of precast concrete.

Last Answer : Advantages: 1. Very rapid speed of erection 2. Good quality control 3. Entire building can be precast-walls, floors, beams, etc. 4. Rapid construction on site 5. High quality because of ... is required in the application of the panel on site. 11. Cranes are required to lift panels.

State any four situations where hollow concrete block masonry is used.

Description : State any four situations where hollow concrete block masonry is used.

Last Answer : Situations where hollow concrete block masonry is used. 1) Hollow concrete blocks are fire resistant and hence are used in masonry where fire resistance is necessary, like furnace, chimney etc. ... . 6) They are used to achieve lower labor involvement and greater durability, like Retaining walls

State four point of differences between reinforced concrete and fibre reinforced concrete.

Description : State four point of differences between reinforced concrete and fibre reinforced concrete.

Last Answer : Differences between reinforced concrete and fibre reinforced concrete:  Sr. No. Reinforced concrete (RCC)  Fibre reinforced concrete (FRC) 1 In this concrete, steel bars are used as ... etc. FRC is used in tunnel lining, runway, aircraft parking, repair of dams, etc.

Columns may be made of plain concrete if their unsupported lengths do not exceed their least lateral dimension (A) Two times (B) Three times (C) Four times (D) Five times

Description : Columns may be made of plain concrete if their unsupported lengths do not exceed their least lateral dimension (A) Two times (B) Three times (C) Four times (D) Five times

Last Answer : Answer: Option C

State any four causes and two effects of earthquake

Description : State any four causes and two effects of earthquake 

Last Answer : Possible cause of an earthquake are classified into below categories i) Movement of tectonic plates ii) Volcanic eruption iii) Anthropogenic sources iv) Dams v) Use of explosives vi) Sport games ... ground rupture. ii) Landslides and Avalanches iii) Fires iv) Soil liquefaction v) Tsunamis

State any four effects of earthquake.

Description : State any four effects of earthquake.

Last Answer : Effect of earthquake: 1. Destruction of various Civil Engineering structures 2. Formation of irregularities (unevenness) on ground 3. Sudden landslides along hill slopes 4. Change in river course 5. ... tidal waves 7. Fire exposure due to short circuiting 8. Loss of human life and property

What are causes of faults in power system? State any four harmful effects of faults.

Description : What are causes of faults in power system? State any four harmful effects of faults.

Last Answer : Causes of Faults in the Power System:  1) Breaking of Conductors: It is one of major causes of faults. Breaking of conductors is due to excessive heat or because of mechanical stresses ... maintenance of machines / equipment / lines / protective system leads to faults in the power system.