The phrase "unaltered form" is correct and usable in written English.
It is typically used to describe a version of something that has not been changed or modified in any way. For example, "All students must submit their essays in unaltered form."
Sometimes it is the natural environment in largely unaltered form.
By his own standard that means the films now belong to audiences, in their original, unaltered form.
In the last film that he directed, "Pa Parade," Tati performed, in refined but essentially unaltered form, his sporting impressions; he was back where he began...
He argues that returning food to the most basic, unaltered form is the best solution not just for taste but health.
The F.D.A. provides device makers with the reports in an unaltered form, and they may contain criticisms of a company's procedures.
Next Saturday the ensemble will perform Mr. Harvey's "Bird Concerto With Pianosong" (2001), in which he incorporates digital recordings of 40 birds, heard in both unaltered form and electronically transformed into different timbres and sonorities with a synthesizer.
Most studies and regulations of air pollutants address individual substances in their unaltered primary form.
As shown in Table 3 for all substrates tested, this variant showed an unaltered activity and formed a similar set of products as the wild type enzyme.
If the stored information, in unaltered or changed form, can be passed on to the progeny, we then have to deal with the phenomenon of inheritance.
During exhalation, peak expiratory flow, mean expiratory flow, and the ratio of the duration of expiration to that of one full breath were unaltered by any form of positive airway pressure (Table 1).
The dynamic characteristics of the total respiratory system (lungs plus chest wall) were unaffected by IPAP and CPAP but were reduced with the use of EPAP (P < 0.05), whereas measures of dynamic chest wall mechanics were unaltered by any form of positive airway pressure (Table 1).
